GB2275783A - Low voltage detection circuit for use in a remote control unit - Google Patents

Low voltage detection circuit for use in a remote control unit Download PDF

Info

Publication number
GB2275783A
GB2275783A GB9403929A GB9403929A GB2275783A GB 2275783 A GB2275783 A GB 2275783A GB 9403929 A GB9403929 A GB 9403929A GB 9403929 A GB9403929 A GB 9403929A GB 2275783 A GB2275783 A GB 2275783A
Authority
GB
Grant status
Application
Patent type
Prior art keywords
battery
remote control
charging
control unit
means
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB9403929A
Other versions
GB9403929D0 (en )
Inventor
Jr Carlton Jethro Simmons
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Thomson Consumer Electronics Inc
Original Assignee
Thomson Consumer Electronics Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36Apparatus for testing electrical condition of accumulators or electric batteries, e.g. capacity or charge condition
    • G01R31/3644Various constructional arrangements
    • G01R31/3648Various constructional arrangements comprising digital calculation means, e.g. for performing an algorithm

Abstract

A battery monitoring apparatus 110 in a remote control unit measures the time it takes for a charging circuit C160 connected to the battery +V, to charge to a predetermined level. A weak battery takes a longer time to charge than does a fully charged battery. The charging time associated with a fully charged battery is measured by a timer 119 and recorded in a RAM 116 and compared to subsequent charging time measurements. When the difference between the recorded charging time and a currently-measured charging time exceeds a predetermined value, a weak-battery alert signal is generated. In one embodiment, the alert signal is applied to a visible LED driver circuit 170; in another embodiment, the weak=battery alert signal is transmitted to the controlled equipment which alerts the user. <IMAGE>

Description

LOW VOLTAGE DETECTION CIRCUIT FOR USE IN A REMOTE CONTROL UNIT This invention concerns remote control units, in general, and, in particular, a remote control unit having a battery monitoring circuit, and a method of determining the condition of a battery.

r?i'irelzss remote control units for controlling consumer electronic equipment are quite commonplace. The vast majority of these remote control units transmit modulated infrared (IR) signals to their respective devices under control of a microprocessor controller. Batteries are used as the power source for the microprocessor and IR transmitter circuitry of these wireless units. Unfortunately, batteries have a limited useful life, and are said to get "weak' and eventually "die'. At some point the batteries become so weak that the remote control uni: will operate erratically, or cease to operate at all. Some remote control units store user-entered preferences in volatile random access memory (RAM), which is maintained by an applied voltage from the battery. It is noted that a user may expend a considerable amount of time entering preference data during a setup mode of operation. A user may thus be inconvenienced when his remote control loses stored preference data due to the inability of a weak or dead battery to maintain the data in memory. Clearly, a weak battery must be replaced in a timely fashion in order to prevent such a loss of data (normally, a "holding" capacitor is used to maintain a data-holding-voltage on the RAM memory chips while the battery is being replaced with a "fresh" (i.e., fully-charged") one). Thus, there is a need for a reliable weak-battery detector for detecting a weak battery condition and alerting a user that battery failure is imminent.

A prior battery-monitoring circuit is known from the CRK 22A remote control unit manufactured by RCA Corporation, Indianapolis, Indiana, and sold with the CTC 74 and CTC 81 color television chassis. In that prior circuit, the battery voltage was not monitored automatically and continually, but rather was monitored only when a particular keyswitch was pressed.

Moreover1 the monitoring circuit employed a programmable unijunction transistor (PUT) biased to operate at a particular voltage by a voltage divider including an adjustment potentiometer. In such an arrangement, factory adjustment of the voltage divider is required to ensure proper operation, because each PUT has slightly different characteristics, and because the potentiometer must be preset in the correct range. It is clearly desirable to eliminate the potentiometer and its required factory set-up adjustment, and to provide for continual monitoring of the battery condition.

According to a first aspect of the present invention there is provided a remote control unit including a battery monitoring circuit for monitoring the condition of a battery, comprising: charging means for charging to a predetermined level; switch means for coupling said charging means to one terminal of said battery for applying battery voltage to said charging means; a controller coupled to said switch means for controlling said switch means to apply said battery voltage to said charging means; and timer means under control of said controller for timing a period; said controller repeatedly timing a time period beginning when said switch means applies said battery voltage to said charging means and ending when said charging means charges to said predetermined level; said controller generating an alarm signal when the duration of said time period exceeds a predetermined value.

Thus in accordance with the invention, a battery monitoring apparatus in a remote control unit measures the time it takes for a charging circuit to charge from a discharged condition to a predetermined level. A weak battery takes a longer time to charge the charging circuit to the predetermined level than does a fully charged battery. The charging time associated with a fully charged battery is recorded and compared to subsequent charging time measurements. When the difference between the recorded charging time and a currently-measured charging time exceeds a predetermined value, a weak-batiery alert signal is generated. In one embodlrnent, the alert signal is applied to a visible LED, in another embodiment, the weak-battery alert signal is transmitted to the controlled equipment which alerts the user.

According to a second aspect of the present invention, there is provided a method of determining the condition of a battery, comprising the steps of: scharging a charging cirzi; applying voltage of said battery to said charging circuit; timing the period in which said charging circui charges to a predetermined threshold level; recording said period after the first measurement; repeating said steps and comparing each new timed period to said recorded period; and generating an alarm signal if one of said new tined periods is greater than said recorded period by a predetermined amount.

A preferred embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, of which: FIGURE 1 is an illustration of a remote control unit having a battery condition monitor in accordance with the invention FIGURES 2 and 3 are graphs of voltage with respect to time which are helpful in understanding the invention; and FIGURE 4 is an illustration of a simplified flowchart showing a portion of the program code of controller 110 of FIGURE 1.

Referring to FIGURE 1, a remote control unit includes a microcomputer 110 for reading inputs of a keyboard, generally designated 120, and applying signals to be transmitted to an infrared (IR) LED transmitter arrangement, generally designated 140. The terms "microcomputer", "controller", and "microprocessor", as used herein, are equivalent. It is also recognized that the control function of microcomputer 110 may be performed by an integrated circuit especially manufactured for that specific purpose (i.e., a "custom chip"), and the term "controller", as used herein, is also intended to include such a device. Microcomputer 110 receives user-initiated commands from keyboard 120 which is mounted on the remote control unit.

Microcomputer 110 includes a central processing unit (CPU) 112, a program memory (ROM) 114, and includes a random-access memory (RAM) 116. ROM 114 may be either internal to, or external to, microprocessor 110, and may also contain preprogrammed control codes for various equipment of different manufacturers. If so, RAM 116 may be used for expansion of the particular compressed set of control codes selected for each device to be controlled. Controller 110 also includes a TINKER 119, the function of which will be described below. IR LED transmitter arrangement 140, includes an IR LED designated LED 140, a driver transistor Q140, current-limiting resistors R140 and R142, and a filter capacitor C140.

Keyboard 120 includes, for example, sixteen keys, and has four drive (i.e., input) lines coupled to controller 110 at output ports DO through D3, and four sense (i.e., output) lines coupled to controller 110 at input ports S0 through S3. In operation, keyboard 120 is scanned by applying a high level (i.e., logic level 1) signal to each of drive lines DO through D3, in turn. After the high level signal is moved from one drive line to another, each of sense lines SO through S3 is read to see if a high level signal is present. If so, then one of the keys of keyboard 120 must be down, completing a circuit from the active drive line to the active sense line. Controller 110 can easily determine which key is down because each key affects a unique drive line/sense line pair.

A dotted box 118 encompasses a switch SWl which switches between a source of positive voltage and ground.

Although SW1 is shown for simplicity as a mechanical switch, one skilled in the art will realize that SW1 is intended to be an electronic switch such as a bipolar transistor, or FET, output of controller 110. A battery condition measuring circuit 160, comprises a charging portion including a resistor R160 (approximately 100 kilohms) and a capacitor C160 (approximately .001 microfarads), and a detection portion including a resistor R162 (approximately 10 kilohms) and switching transistor Q160.

FIGURE 2 shows voltage versus time graphs for a fully charged battery. A nominal "5-volt battery" for supplying the +V supply voltage of the embodiment of FIGURE 1 and the graph of FIGURE 2 comprises four 1.5 volt AA batteries and a diode coupled in series (i.e., the actual supply voltage is 6 volts - 0.7 volts = 5.3 volts). At approximately 1 microsecond, a 5 volt positive-going step signal 210, having a rise time of approximately 0.1 microseconds, is applied to charging circuit R160/C160. Capacitor C160 begins charging through resistor R160 as shown in curve 215. When the voltage at the base of transistor Q160 reaches approximately 400 millivolts (at about 9 microseconds), transistor Q160 begins to switch on, reaching a fully on state when its base voltage reaches about 500 millivolts (at approximately 12 microseconds) as shown in curve 220. Thus, curve 220 is at a high level (while capacitor C 160 is charging) for about 11 microseconds, when measuring a battery producing S volts. Transistor Q160 is actually performing as a threshold voltage detector.

FIGURE 3 shows voltage versus time graphs for a weak (i.e. 4 volt) battery. At approximately 1 microsecond, a 4 volt positive-going step signal 310, having a rise time of approximately 0.1 microseconds, is applied to charging circuit R160/C160. Capacitor C160 begins charging through resistor R160 as shown in curve 315. When the voltage at the base of transistor Q160 reaches approximately 400 millivolts (at about 11 microseconds), transistor Q160 begins to switch on, reaching a fully on state when its base voltage reaches about 500 millivolts (at approximately 14 microseconds) as shown in curve 320. Thus, curve 320 is at a high level (while capacitor C160 is charging) for about 13 microseconds, when measuring a weaker battery (i.e., one producing only 4 volts). It is noted that it takes longer to get to a fixed predetermined voltage level in the case of the weaker battery with lower terminal voltage, because the charging rate dv/dt is lower in the case of the weak battery. That is, capacitor C160 will be fully charged in approximately five time constants.

The duration of the time constant is fixed and determined by the values of R160 and C160. Therefore, in the case of a weak battery, the charging rate is lower because capacitor 160 is charging to a lower voltage in the same amount of time.

Transistor Q160 will switch later when measuring a weak battery because the switching point of transistor Q160 is substantially fixed, as shown in FIGURES 2 and 3, at about 500 millivolts, and because the voltage across capacitor 160 (i.e., the switching voltage for transistor Q160) will develop over a longer period of time due to the lower charging rate. It is herein recognized that measuring the charging period and detecting a change to a longer period is an effective and reliable way to detect a weak battery condition.

Note that the actual switching point of transistor Q160 is not critical, because it will be automatically compensated for in each measurement. Note also that in the case of a weak battery, the lower switching point of controller 110 will be lowered farther (i.e.,. from about 1.5 volts guaranteed low when the supply voltage is 5 volts, to about 1.1 volts guaranteed low when the supply voltage is 4 volts). The lowering of the lower switch point of controller 110 will further delay the detection of the switching of transistor Q160 by approximately 100 nanoseconds, which is in a direction to aid in the detection of a weak battery.

As shown in the flowchart of FIGURE 4, the measurement routine is entered at step 400, where, in order to fully discharge capacitor C160 in preparation for measuring battery condition, microprocessor 110 sets switch SWI to apply a low level signal to capacitor C160 via resistor R160. At step 410 a 100 microsecond delay is executed to allow for the discharge of capacitor C160. At step 415, switch SW1 is switched to apply the full supply voltage to monitoring circuit 160, and TIMER 119 is started. At step 420, sense line S4 is checked for the presence of a low level signal. If a low level signal is not present, then transistor Q160 has not yet switched on, and the program loops around to step 420 again. If a low level signal is present, then transistor Q160 has switched on and the YES path is followed to step 425. At step 425, a check is made to determine if this is the first time through this routine (i.e., the first time the remote control unit has been powered-up). If so, the FIRST TIME FLAG (i.e., a location in RAM 116) will not be set, and the routine will advance to step 430. At step 430, TINIER 119 will be stopped and read, its value stored in RAM 116 and the FIRST TIME FLAG will be set. The routine will then be exited via step 450. Each time that the remote control unit is operated, this routine will once again be entered, and the measurement taken at steps 400-420.

At step 425, however, the FIRST TIME FLAG will be set. This causes the routine to advance to step 435, at which TIMER 119 is stopped, its value read, and the previously-stored value subtracted from the currently-read value. If the readings differ by more than a predetermined amount (e.g., 2 microseconds) the YES path is followed to step 440 at which a WEAK BATTERY ALARM signal is generated, and the routine exited at step 450. If the readings at step 435 do not differ by the predetermined amount then the NO path is taken to the exit at step 450. It is recognized that the function of TIMER 119 may be performed without an actual hardware timer, by counting instruction cycles or decrementing the value of a count in a memory location.

In a first embodiment of the subject invention a visible-light-emitting diode (VLED) designated VLED 170 is illuminated by a WEAK BATTERY ALARM signal applied to a VLED driver circuit 170, via a current-limiting resistor R170. VLED driver arrangement 170, includes an visible-LED designated VLED 170, a driver transistor Q170, current-limiting resistors R170 and R172, and a filter capacitor C170.

In a second embodiment of the invention, VLED driver arrangement 170 is not required, because the WEAK BATTERY ALARM signal is a remote control code signal which is transmitted to the device to be controlled, which has a weak-battery warning message or symbol stored in its own ROM, and in turn alerts the user to the weak battery condition. In the event that the device to be controlled is a video device (i.e., television set, video monitor, VCR, or videodisc player), then an on-screen message can be generated to warn the user of impending battery failure.

It should also be noted that switch SW1 performs a second function in shutting down measurement circuit 160 when controller 110 enters the sleep mode. This is accomplished by switching SWI to apply a low level signal to measurement circuit 160, causing it to draw no current.

Thus, an arrangement has been described which provides for effective and reliable monitoring of the condition of a battery in a remote control unit. Although an IR remote control is shown in the embodiments of FIGURES 1 and 3, one skilled in the art should be aware that the invention is also applicable to remote control units which transmit radio frequency (RF) signals, and such remote control units are deemed to be within the scope of the invention. Although an IR remote control is shown in the embodiments of FIGURES 1 and 3, it is recognized that the invention is not limited to applications in remote control units, but rather may be used in other battery-powered equipment.

Claims (10)

1. A remote control unit including a battery monitoring circuit for monitoring the condition of a battery, comprising: charging means for charging to a predetermined level; switch means for coupling said charging means to one terminal of said battery for applying battery voltage to said charging means; a controller coupled to said switch means for controlling said switch means to apply said battery voltage to said charging means; and timer means under control of said controller for timing a period; said controller repeatedly timing a time period beginning when said switch means applies said battery voltage to said charging means and ending when said charging means charges to said predetermined level; said controller generating an alarm signal when the duration of said time period exceeds a predetermined value.
2. The remote control unit of claim 1, wherein said switch means has a first position for discharging said charging means and a second position for applying said battery voltage to said charging means.
3. The remote control unit of claim 1 or 2 wherein said switch means is an output port of said controller.
4. The remote control unit of any preceding claim, further including threshold detection means for detecting a development of a signal across said charging means at said predetermined level.
5. The remote control unit of claim 4, wherein said threshold detection means is a transistor.
6. The remote control unit of any preceding claim, wherein said alarm signal is applied to a visible LED.
7. The remote control unit of any of claims 1 to 5, wherein said alarm signal is transmitted to a device to be controlled, which device alerts a user to imminent battery failure.
8. A remote control unit substantially as herein described with reference to the accompanying drawings.
9. A method of determining the condition of a battery, comprising the steps of: discharging a charging circuit; applying voltage of said battery to said charging circuit; timing the period in which said charging circuit charges to a predetermined threshold level; recording said period after the first measurement; repeating said steps and comparing each new timed period to said recorded period; and generating an alarm signal if one of said new timed periods is greater than said recorded period by a predetermined amount.
10. A method of determining the condition of a battery substantially as herein described with reference to the accompanying drawings.
GB9403929A 1993-03-02 1994-03-01 Low voltage detection circuit for use in a remote control unit Withdrawn GB2275783A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US1809593 true 1993-03-02 1993-03-02

Publications (2)

Publication Number Publication Date
GB9403929D0 true GB9403929D0 (en) 1994-04-20
GB2275783A true true GB2275783A (en) 1994-09-07

Family

ID=21786206

Family Applications (1)

Application Number Title Priority Date Filing Date
GB9403929A Withdrawn GB2275783A (en) 1993-03-02 1994-03-01 Low voltage detection circuit for use in a remote control unit

Country Status (3)

Country Link
JP (1) JPH06276587A (en)
CN (1) CN1093811A (en)
GB (1) GB2275783A (en)

Cited By (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2416215A (en) * 2004-07-12 2006-01-18 Midtronics Inc Wireless battery tester
EP1918728A1 (en) * 2006-10-24 2008-05-07 Honeywell International Inc. Lithium-ion battery diagnostic and prognostic techniques
CN100489736C (en) 2002-11-25 2009-05-20 神基科技股份有限公司 Method for accessing battery state by operation system of portable computer
US7656162B2 (en) 1996-07-29 2010-02-02 Midtronics Inc. Electronic battery tester with vehicle type input
US7688074B2 (en) 1997-11-03 2010-03-30 Midtronics, Inc. Energy management system for automotive vehicle
US7706991B2 (en) 1996-07-29 2010-04-27 Midtronics, Inc. Alternator tester
US7705602B2 (en) 1997-11-03 2010-04-27 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US7710119B2 (en) 2004-12-09 2010-05-04 Midtronics, Inc. Battery tester that calculates its own reference values
US7728597B2 (en) 2000-03-27 2010-06-01 Midtronics, Inc. Electronic battery tester with databus
US7774151B2 (en) 1997-11-03 2010-08-10 Midtronics, Inc. Wireless battery monitor
US7777612B2 (en) 2004-04-13 2010-08-17 Midtronics, Inc. Theft prevention device for automotive vehicle service centers
US7791348B2 (en) 2007-02-27 2010-09-07 Midtronics, Inc. Battery tester with promotion feature to promote use of the battery tester by providing the user with codes having redeemable value
US7808375B2 (en) 2007-04-16 2010-10-05 Midtronics, Inc. Battery run down indicator
US7977914B2 (en) 2003-10-08 2011-07-12 Midtronics, Inc. Battery maintenance tool with probe light
US7999505B2 (en) 1997-11-03 2011-08-16 Midtronics, Inc. In-vehicle battery monitor
US8164343B2 (en) 2003-09-05 2012-04-24 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US8198900B2 (en) 1996-07-29 2012-06-12 Midtronics, Inc. Automotive battery charging system tester
US8203345B2 (en) 2007-12-06 2012-06-19 Midtronics, Inc. Storage battery and battery tester
US8237448B2 (en) 2000-03-27 2012-08-07 Midtronics, Inc. Battery testers with secondary functionality
US8306690B2 (en) 2007-07-17 2012-11-06 Midtronics, Inc. Battery tester for electric vehicle
US8344685B2 (en) 2004-08-20 2013-01-01 Midtronics, Inc. System for automatically gathering battery information
US8436619B2 (en) 2004-08-20 2013-05-07 Midtronics, Inc. Integrated tag reader and environment sensor
US8442877B2 (en) 2004-08-20 2013-05-14 Midtronics, Inc. Simplification of inventory management
US8513949B2 (en) 2000-03-27 2013-08-20 Midtronics, Inc. Electronic battery tester or charger with databus connection
US8674711B2 (en) 2003-09-05 2014-03-18 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US8738309B2 (en) 2010-09-30 2014-05-27 Midtronics, Inc. Battery pack maintenance for electric vehicles
US8872517B2 (en) 1996-07-29 2014-10-28 Midtronics, Inc. Electronic battery tester with battery age input
US8958998B2 (en) 1997-11-03 2015-02-17 Midtronics, Inc. Electronic battery tester with network communication
US9018958B2 (en) 2003-09-05 2015-04-28 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9201120B2 (en) 2010-08-12 2015-12-01 Midtronics, Inc. Electronic battery tester for testing storage battery
US9229062B2 (en) 2010-05-27 2016-01-05 Midtronics, Inc. Electronic storage battery diagnostic system
US9244100B2 (en) 2013-03-15 2016-01-26 Midtronics, Inc. Current clamp with jaw closure detection
US9255955B2 (en) 2003-09-05 2016-02-09 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9274157B2 (en) 2007-07-17 2016-03-01 Midtronics, Inc. Battery tester for electric vehicle
US9312575B2 (en) 2013-05-16 2016-04-12 Midtronics, Inc. Battery testing system and method
US9419311B2 (en) 2010-06-18 2016-08-16 Midtronics, Inc. Battery maintenance device with thermal buffer
US9425487B2 (en) 2010-03-03 2016-08-23 Midtronics, Inc. Monitor for front terminal batteries
US9496720B2 (en) 2004-08-20 2016-11-15 Midtronics, Inc. System for automatically gathering battery information
US9588185B2 (en) 2010-02-25 2017-03-07 Keith S. Champlin Method and apparatus for detecting cell deterioration in an electrochemical cell or battery
US9851411B2 (en) 2012-06-28 2017-12-26 Keith S. Champlin Suppressing HF cable oscillations during dynamic measurements of cells and batteries
US9923289B2 (en) 2014-01-16 2018-03-20 Midtronics, Inc. Battery clamp with endoskeleton design
US9966676B2 (en) 2015-09-28 2018-05-08 Midtronics, Inc. Kelvin connector adapter for storage battery
US10046649B2 (en) 2012-06-28 2018-08-14 Midtronics, Inc. Hybrid and electric vehicle battery pack maintenance device

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100510757C (en) 2007-05-23 2009-07-08 智原科技股份有限公司 Over-voltage indication circuit and system circuit and method
US20090102672A1 (en) 2007-10-19 2009-04-23 Honeywell International, Inc. Features to reduce low-battery reporting to security services at night
CN101923770B (en) 2009-06-11 2013-01-09 鸿富锦精密工业(深圳)有限公司 Remote controller and electric quantity prompt system
CN104062591B (en) * 2013-03-22 2017-06-23 海洋王(东莞)照明科技有限公司 A battery low voltage alarm circuit

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2167869A (en) * 1984-11-28 1986-06-04 Telectronics Nv Testing batteries
EP0501165A1 (en) * 1991-02-21 1992-09-02 Loewe Opta Gmbh State of charge indicator for a battery or an accumulator in a remote control transmitter

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2167869A (en) * 1984-11-28 1986-06-04 Telectronics Nv Testing batteries
EP0501165A1 (en) * 1991-02-21 1992-09-02 Loewe Opta Gmbh State of charge indicator for a battery or an accumulator in a remote control transmitter

Cited By (56)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7706991B2 (en) 1996-07-29 2010-04-27 Midtronics, Inc. Alternator tester
US8198900B2 (en) 1996-07-29 2012-06-12 Midtronics, Inc. Automotive battery charging system tester
US8872517B2 (en) 1996-07-29 2014-10-28 Midtronics, Inc. Electronic battery tester with battery age input
US7656162B2 (en) 1996-07-29 2010-02-02 Midtronics Inc. Electronic battery tester with vehicle type input
US7940052B2 (en) 1996-07-29 2011-05-10 Midtronics, Inc. Electronic battery test based upon battery requirements
US8674654B2 (en) 1997-11-03 2014-03-18 Midtronics, Inc. In-vehicle battery monitor
US7688074B2 (en) 1997-11-03 2010-03-30 Midtronics, Inc. Energy management system for automotive vehicle
US8958998B2 (en) 1997-11-03 2015-02-17 Midtronics, Inc. Electronic battery tester with network communication
US7705602B2 (en) 1997-11-03 2010-04-27 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US7999505B2 (en) 1997-11-03 2011-08-16 Midtronics, Inc. In-vehicle battery monitor
US7774151B2 (en) 1997-11-03 2010-08-10 Midtronics, Inc. Wireless battery monitor
US8493022B2 (en) 1997-11-03 2013-07-23 Midtronics, Inc. Automotive vehicle electrical system diagnostic device
US8754653B2 (en) 1999-11-01 2014-06-17 Midtronics, Inc. Electronic battery tester
US9052366B2 (en) 2000-03-27 2015-06-09 Midtronics, Inc. Battery testers with secondary functionality
US8237448B2 (en) 2000-03-27 2012-08-07 Midtronics, Inc. Battery testers with secondary functionality
US7728597B2 (en) 2000-03-27 2010-06-01 Midtronics, Inc. Electronic battery tester with databus
US7924015B2 (en) 2000-03-27 2011-04-12 Midtronics, Inc. Automotive vehicle battery test system
US8872516B2 (en) 2000-03-27 2014-10-28 Midtronics, Inc. Electronic battery tester mounted in a vehicle
US8513949B2 (en) 2000-03-27 2013-08-20 Midtronics, Inc. Electronic battery tester or charger with databus connection
CN100489736C (en) 2002-11-25 2009-05-20 神基科技股份有限公司 Method for accessing battery state by operation system of portable computer
US8674711B2 (en) 2003-09-05 2014-03-18 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US8164343B2 (en) 2003-09-05 2012-04-24 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9018958B2 (en) 2003-09-05 2015-04-28 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US9255955B2 (en) 2003-09-05 2016-02-09 Midtronics, Inc. Method and apparatus for measuring a parameter of a vehicle electrical system
US7977914B2 (en) 2003-10-08 2011-07-12 Midtronics, Inc. Battery maintenance tool with probe light
US7777612B2 (en) 2004-04-13 2010-08-17 Midtronics, Inc. Theft prevention device for automotive vehicle service centers
US7772850B2 (en) 2004-07-12 2010-08-10 Midtronics, Inc. Wireless battery tester with information encryption means
GB2416215A (en) * 2004-07-12 2006-01-18 Midtronics Inc Wireless battery tester
US8442877B2 (en) 2004-08-20 2013-05-14 Midtronics, Inc. Simplification of inventory management
US8436619B2 (en) 2004-08-20 2013-05-07 Midtronics, Inc. Integrated tag reader and environment sensor
US8344685B2 (en) 2004-08-20 2013-01-01 Midtronics, Inc. System for automatically gathering battery information
US9496720B2 (en) 2004-08-20 2016-11-15 Midtronics, Inc. System for automatically gathering battery information
US8704483B2 (en) 2004-08-20 2014-04-22 Midtronics, Inc. System for automatically gathering battery information
US8963550B2 (en) 2004-08-20 2015-02-24 Midtronics, Inc. System for automatically gathering battery information
US7710119B2 (en) 2004-12-09 2010-05-04 Midtronics, Inc. Battery tester that calculates its own reference values
US7612540B2 (en) * 2006-10-24 2009-11-03 Honeywell International Inc. Lithium-ion battery diagnostic and prognostic techniques
EP1918728A1 (en) * 2006-10-24 2008-05-07 Honeywell International Inc. Lithium-ion battery diagnostic and prognostic techniques
US7940053B2 (en) 2007-02-27 2011-05-10 Midtronics, Inc. Battery tester with promotion feature
US7791348B2 (en) 2007-02-27 2010-09-07 Midtronics, Inc. Battery tester with promotion feature to promote use of the battery tester by providing the user with codes having redeemable value
US7808375B2 (en) 2007-04-16 2010-10-05 Midtronics, Inc. Battery run down indicator
US9335362B2 (en) 2007-07-17 2016-05-10 Midtronics, Inc. Battery tester for electric vehicle
US8306690B2 (en) 2007-07-17 2012-11-06 Midtronics, Inc. Battery tester for electric vehicle
US9274157B2 (en) 2007-07-17 2016-03-01 Midtronics, Inc. Battery tester for electric vehicle
US8203345B2 (en) 2007-12-06 2012-06-19 Midtronics, Inc. Storage battery and battery tester
US9588185B2 (en) 2010-02-25 2017-03-07 Keith S. Champlin Method and apparatus for detecting cell deterioration in an electrochemical cell or battery
US9425487B2 (en) 2010-03-03 2016-08-23 Midtronics, Inc. Monitor for front terminal batteries
US9229062B2 (en) 2010-05-27 2016-01-05 Midtronics, Inc. Electronic storage battery diagnostic system
US9419311B2 (en) 2010-06-18 2016-08-16 Midtronics, Inc. Battery maintenance device with thermal buffer
US9201120B2 (en) 2010-08-12 2015-12-01 Midtronics, Inc. Electronic battery tester for testing storage battery
US8738309B2 (en) 2010-09-30 2014-05-27 Midtronics, Inc. Battery pack maintenance for electric vehicles
US10046649B2 (en) 2012-06-28 2018-08-14 Midtronics, Inc. Hybrid and electric vehicle battery pack maintenance device
US9851411B2 (en) 2012-06-28 2017-12-26 Keith S. Champlin Suppressing HF cable oscillations during dynamic measurements of cells and batteries
US9244100B2 (en) 2013-03-15 2016-01-26 Midtronics, Inc. Current clamp with jaw closure detection
US9312575B2 (en) 2013-05-16 2016-04-12 Midtronics, Inc. Battery testing system and method
US9923289B2 (en) 2014-01-16 2018-03-20 Midtronics, Inc. Battery clamp with endoskeleton design
US9966676B2 (en) 2015-09-28 2018-05-08 Midtronics, Inc. Kelvin connector adapter for storage battery

Also Published As

Publication number Publication date Type
JPH06276587A (en) 1994-09-30 application
CN1093811A (en) 1994-10-19 application
GB9403929D0 (en) 1994-04-20 application

Similar Documents

Publication Publication Date Title
US5115182A (en) Battery charging controller for a battery powered device and method for using the same
US4344071A (en) Light switching mechanism
US6232747B1 (en) Remaining-amount-of-battery detecting device
US6188202B1 (en) Battery charging device
US4714915A (en) Portable electrostatic field safety monitor
US5633573A (en) Battery pack having a processor controlled battery operating system
US5055763A (en) Electronic battery charger device and method
US5957374A (en) Voltage boosting system and method for electronic thermostat relay
US5619196A (en) Single wire keyboard encode and decode circuit
US5495093A (en) Soldering apparatus processor having temperature selection, calibration and heating control of tip
US5747969A (en) Method of charging a rechargeable battery with pulses of a predetermined amount of charge
US5608304A (en) Battery protection circuit and battery pack and apparatus using the battery pack
US4278968A (en) Door status detector apparatus
US4931737A (en) Circuit for measuring the capacity of a battery
US5555725A (en) Control system for electrically heated catalyst of internal combustion engine
US5783998A (en) Battery pack, method and electronic device for controlling its operation device
US5163063A (en) Semiconductor laser driving circuit
US6440602B1 (en) Battery pack
US5539297A (en) Charging device for charging a plurality of batteries based on parameter priority
US4429236A (en) Apparatus for generating pulses upon decreases in supply voltage
US4005344A (en) Protection circuit for battery powered electronic devices
US4800336A (en) Battery level indicator supplying data from a memory to a display in a power-off state
US5144218A (en) Device for determining the charge condition of a battery
US5438248A (en) Method and apparatus for recognizing different types of batteries
US5504416A (en) Battery charger circuit including battery temperature control

Legal Events

Date Code Title Description
WAP Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1)