CN207283524U

CN207283524U - Human body sensor circuit

Info

Publication number: CN207283524U
Application number: CN201720406186.XU
Authority: CN
Inventors: 廖焕军
Original assignee: Shenzhen Hejiayuan Network Technology Co Ltd
Current assignee: Shenzhen Hejiayuan Network Technology Co Ltd
Priority date: 2017-04-18
Filing date: 2017-04-18
Publication date: 2018-04-27
Anticipated expiration: 2027-04-18

Abstract

A kind of human body sensor circuit, including single-button soft-touch control chip U1, single-pole double throw electronic switch chip U2, metal PAD, the OUT terminal of the chip U1 is connected by the GPIO2 ends of resistance R2 and MCU chip, HLD ends are connected by the GPIO3 ends of pull-up resistor R3 and MCU chip, OLH ends are connected by the GPIO3 ends of pull-up resistor R5 and MCU chip, the TCH ends of the chip U1 are connected by resistance R4 with the A/COM ends of chip U2, the B0/NC ends connection reference capacitance C3 of the chip U2, the metal PAD is connected with the B1/NO ends of chip U2, the S/IN ends of the chip U2 and the GPIO1 ends of MCU chip connect.The utility model human body sensor circuit, carries out self-calibrating by reference to capacitance C3, avoids erroneous trigger, and circuit is simple, highly practical, reduces power consumption.

Description

Human body sensor circuit

Technical field

Sensor field is the utility model is related to, espespecially a kind of human body sensor circuit.

Background technology

Since mutual capacitance detection technique and modern communications technology are very close, can be transplanted to mutually using existing mature technology Capacitive touch screen detection field, easily designs the product of high-performance, high stability, but its design difficulty is larger, and Chip cost is higher.And self-capacitance detection technique, realize that simply, cost is relatively low, but is highly susceptible to disturb during tim e- domain detection, Properties of product are relatively low.

In the existing human body sensor using self-capacitance detection technique, MCU chip can learn week automatically after the power is turned on The capacitance of surrounding environment, the change of voltage is detected by ADC inside MCU chip, so as to export high level signal, differentiates that human body touches Touch or close.But PAD is touched or proximated to if in human body before powering on, it can not judge, erroneous trigger easily occur； If human body touchs or proximates to PAD again after the power-up, in order to maintain the accuracy of judgement, it is necessary to power on always, power consumption is big.

Utility model content

To solve the above problems, the utility model provides one kind on the basis of original human body sensor circuit, By increasing peripheral circuit, the erroneous trigger in self-capacitance detection technique is solved the problems, such as.

To achieve the above object, the technical solution adopted in the utility model is：A kind of human body sensor circuit, including Single-button soft-touch control chip U1, single-pole double throw electronic switch chip U2, metal PAD, the OUT terminal of the chip U1 pass through resistance The GPIO2 ends of R2 and MCU chip connect, and the vdd terminal of the chip U1 and the GPIO3 ends of MCU chip connect, and HLD ends pass through upper The GPIO3 ends of pull-up resistor R3 and MCU chip connect, and OLH ends are connected by the GPIO3 ends of pull-up resistor R5 and MCU chip, institute The TCH ends for stating chip U1 are connected by resistance R4 with the A/COM ends of chip U2, and the B0/NC ends connection of the chip U2 is with reference to electricity Hold C3, the metal PAD is connected with the B1/NO ends of chip U2, and the S/IN ends of the chip U2 and the GPIO1 ends of MCU chip connect Connect, the VCC ends of the chip U2 and the GPIO3 ends of MCU chip connect.

Specifically, the TCH ends of the chip U1 connect GND ends by capacitance C2, and vdd terminal connects GND ends by capacitance C1.

Specifically, the S/IN ends of the chip U2 connect GND ends by resistance R1, and VCC ends connect GND ends by capacitance C4.

Specifically, the GPIO1 ends, GPIO2 ends, GPIO3 ends level are consistent.

The beneficial effects of the utility model are：The utility model human body sensor circuit, by reference to capacitance C3 Self-calibrating is carried out, so as to judge whether just there is human contact or close PAD before powering on, avoids erroneous trigger, circuit is simple, Highly practical, system need not power on for a long time, and chip will not work long hours, and reduce power consumption, solve self-capacitance detection skill In art the problem of erroneous trigger.

Brief description of the drawings

Fig. 1 is the circuit diagram of the utility model.

Embodiment

Refering to Figure 1, the utility model is on a kind of human body sensor, including single-button soft-touch control chip U1, single-pole double throw electronic switch chip U2, metal PAD, the OUT terminal of the chip U1 pass through resistance R2 and the GPIO2 of MCU chip The GPIO3 ends of end connection, the vdd terminal of the chip U1 and MCU chip connect, and HLD ends pass through pull-up resistor R3 and MCU chip GPIO3 ends connect, and OLH ends are connected by the GPIO3 ends of pull-up resistor R5 and MCU chip, and the TCH ends of the chip U1 pass through Resistance R4 is connected with the A/COM ends of chip U2, B0/NC ends connection the reference capacitance C3, the metal PAD and core of the chip U2 The B1/NO ends connection of piece U2, the S/IN ends of the chip U2 and the GPIO1 ends of MCU chip connect, the VCC ends of the chip U2 It is connected with the GPIO3 ends of MCU chip.

Compared with prior art, the utility model human body sensor circuit, self school is carried out by reference to capacitance C3 Standard, so as to judge whether just there is human contact or close PAD before powering on, avoids erroneous trigger, and circuit is simple, highly practical, System need not power on for a long time, and chip will not work long hours, and reduce power consumption, solve mistake in self-capacitance detection technique and touch The problem of hair.

Specifically, the GPIO1 ends, GPIO2 ends, GPIO3 ends level are consistent.

The utility model is further described below by specific embodiment.

This specific implementation spr chip U1 can use JR9801B chips, CT8223 chips or QM301 chips, and chip U2 can To use BCT4157 chips or SGM3157 chips.

The OLH ends acquiescence of chip U1 pins 4 drags down, and is exported by the OUT terminal of pin 1, and when triggering successfully, output is high Level is effective；The resistance R3 of the OLH ends connection of pin 4 reserves pull-up, and is exported by the OUT terminal of pin 1, when triggering successfully, It is effective to export low level.The HLD ends acquiescence of chip U1 pins 6 drags down, and is exported by the OUT terminal synchronous mode of pin 1, i.e., When the OUT terminal output high level of pin 1 is effective, triggering output is high, and it is low not trigger output；Otherwise the HLD ends of pin 6 pass through resistance R5 pull-up is high, to keep pattern output, that is, triggers the OUT terminal output height of pin 1, it is low that disengaging triggers output again.Chip U1 draws The TCH ends of foot 3 are connected with the A/COM ends of chip U2 pins 4, detection metal PAD.The S/IN ends of its chips U2 pins 5 are electricity Sub switch control logic pin, GND ends are pulled down to by the resistance R1 of 10K so that the B0/ of chip U2 pins 3 is given tacit consent to when powering on NC ends and the conducting of the A/COM ends of pin 4, capacitance C3 is reference capacitance, size is adjusted according to complete machine capacitive environment, so as to subtract The false judgment of few U1.

Wherein, the OLH ends of this specific embodiment human body sensor circuit chip U1 pins 4, chip internal acquiescence are drawn Low, the HLD ends chip internal acquiescence of chip U1 pins 6 drags down, its control logic is as follows：

1）When MCU chip control GPIO1 ends drag down, GPIO3 ends output high level, powers to whole circuit,

2）Be delayed 500ms, and chip U2 turns on the B0/NC ends of pin 3 and the A/COM ends of pin 4, and chip U1 passes through pin 3 TCH ends detection reference capacitance value, completes self-calibrating,

3）MCU chip controls GPIO1 are drawn high at end, and chip U2 turns on the B1/NO ends of pin 1 and the A/COM ends of pin 4, Chip U1 detects metal PAD by chip U2,

4）Be delayed 10ms, and the level at MCU chip detection GPIO2 ends, if high level, judgement is to sense human body, such as Fruit is low level, and judgement is to be not sensed by human body.

5）MCU chip controls GPIO1 ends drag down, and GPIO3 ends output low level, initializes whole circuit.

To improve accuracy, circuit can repeatedly carry out single detection, in follow-up 5 times are detected, not sense human body, Then judge not sense human body, in detecting in follow-up 5 times, as long as once detection senses human body, be judged as feeling Human body should be arrived.Solve in self-capacitance detection technique, even if human body sensor has been contacted before system electrification, can also examine Measure and whether sense human body.

Embodiment of above is only that the preferred embodiment of the utility model is described, not to the utility model Scope be defined, on the premise of the spirit of the design of the utility model is not departed from, this area ordinary skill technical staff to this The various modifications and improvement that the technical solution of utility model is made, should all fall into the guarantor that claims of the utility model determine In the range of shield.

Claims

A kind of 1. human body sensor circuit, it is characterised in that：Including single-button soft-touch control chip U1, single-pole double throw electronics Switch chip U2, metal PAD, wherein the chip U1 is JR9801B chips or CT8223 chips or QM301 chips, the core Piece U2 is BCT4157 chips or SGM3157 chips；The OUT terminal of the chip U1 passes through resistance R2 and the GPIO2 ends of MCU chip The GPIO3 ends of connection, the vdd terminal of the chip U1 and MCU chip connect, and HLD ends pass through pull-up resistor R3 and MCU chip GPIO3 ends connect, and OLH ends are connected by the GPIO3 ends of pull-up resistor R5 and MCU chip, and the TCH ends of the chip U1 pass through electricity Resistance R4 is connected with the A/COM ends of chip U2, B0/NC ends connection the reference capacitance C3, the metal PAD and chip of the chip U2 The GPIO1 ends of the B1/NO ends connection of U2, the S/IN ends of the chip U2 and MCU chip connect, the VCC ends of the chip U2 with The GPIO3 ends connection of MCU chip.
A kind of 2. human body sensor circuit according to claim 1, it is characterised in that：The TCH ends of the chip U1 GND ends are connect by capacitance C2, vdd terminal connects GND ends by capacitance C1.
A kind of 3. human body sensor circuit according to claim 1, it is characterised in that：The S/IN ends of the chip U2 GND ends are connect by resistance R1, VCC ends connect GND ends by capacitance C4.
A kind of 4. human body sensor circuit according to claim 1, it is characterised in that：The GPIO1 ends, GPIO2 End, GPIO3 ends level are consistent.