CN203117279U

CN203117279U - Power supply and current detection equipment based on testing device for camera module of handset

Info

Publication number: CN203117279U
Application number: CN 201320087744
Authority: CN
Inventors: 张锐; 张扣文; 吴业; 柴奇峰; 丁亮; 陈余天
Original assignee: Ningbo Sunny Opotech Co Ltd
Current assignee: Ningbo Sunny Opotech Co Ltd
Priority date: 2013-02-26
Filing date: 2013-02-26
Publication date: 2013-08-07
Anticipated expiration: 2023-02-26

Abstract

The utility model provides power supply and current detection equipment based on a testing device for the camera module of a handset, which comprises a single-chip microcomputer MEGA 88PA, a chip DAC LTC 1669, a triode, a chip MAX 9611 and a chip DS2745. The single-chip microcomputer MEGA 88PA is respectively connected with the chip DAC LTC 1669, the chip MAX 9611 and the chip DS2745. The chip DAC LTC 1669 is connected with the camera module through the triode. The chip MAX 9611 and the chip DS2745 are connected with the camera module. The single-chip microcomputer MEGA 88PA is also connected with the camera module. Due to the adoption of the equipment, the working current and the standby current can be detected at any time. Meanwhile, due to the application of the single-chip microcomputer, the power supply for adapter boards is more convenient in design. The consumption of low dropout regulators (LDO) of various specifications on adapter boards is lowered, so that the cost is reduced correspondingly. The control over the power-on sequence is also realized.

Description

Power supply supply and current sensing means based on cell-phone camera module checkout equipment

Technical field

The utility model relates to the auxiliary field of image power supply, especially relates to a kind of power supply supply and current sensing means based on cell-phone camera module checkout equipment.

Background technology

Along with on the market to the increase of the demand of high pixel module, the quality of high pixel module has also been proposed more and more higher requirement.0.3M before, 2M, the power-supply system on the testing tool of 3M module is difficult to satisfy the power demands of high pixel module again.The extensive use of ISP on high pixel module, the kind of supply voltage is more, and the electric current demand is bigger; It is very necessary that the electric supply system of design module highlights.

The module complexity of the relative low pixel with circuit of the structure of high pixel module is more, and the probability that high pixel module goes wrong can increase.Not that very important parameters such as working current, standby current will have bigger influence to the performance of high pixel in low pixel module.Module generally is used for portable equipment, and portable equipment is comparatively responsive to working current and the standby current of device, and working current and the standby current of module had comparatively strict requirement.The working current of module and the test of standby current become a kind of necessity.

Controllable electric power can effectively reduce the probability that causes module to damage because of the voltage of dialing the wrong number.Under the situation of not closing total power switch, realize the cold plug of module, stop the damage that causes because of the module hot plug, realized the robotization control of module power supply simultaneously.

Summary of the invention

The utility model provides a kind of power supply supply and current sensing means based on cell-phone camera module checkout equipment, can satisfy the power demands of high pixel module, can carry out size and power supply timing control to the power supply supply voltage of camera module, and the electric current when described device self can be surveyed six tunnel work simultaneously, reduce and use other checkout equipments, easy to use, the precision height, communicating by letter by Single-chip Controlling of device on the described device and host computer evaded I ²The collision problem of C address.Its technical scheme is as described below:

A kind of power supply supply and current sensing means based on cell-phone camera module checkout equipment, comprise single-chip microcomputer MEGA88PA, chip DAC LTC1669, triode, chip MAX9611, chip DS2745, described single-chip microcomputer MEGA88PA is connected with chip DAC LTC1669, chip MAX9611, chip DS2745 respectively, described chip DAC LTC1669 is connected with the camera module by triode, described chip MAX9611, chip DS2745 are connected with the camera module, and described single-chip microcomputer MEGA88PA is connected with the camera module.

Described chip DAC LTC1669 and chip MAX9611 are respectively 6 groups.

Be provided with I between described single-chip microcomputer MEGA88PA and camera module ²The C bus switch, described bus switch adopts chip NC7SZ66.

Be provided with amplifier chip LM2904 between described chip DAC LTC1669 and triode.

The RS+ pin of described chip MAX9611, RS-pin directly are connected on the two ends of sampling resistor, and the inside of chip MAX9611 is provided with special-purpose amplifier, can select the enlargement factor of X1, X4, X8.

Described triode adopts pliotron D1760.

Described power supply supply and current sensing means testing electric current and standby current at any time based on cell-phone camera module checkout equipment, the application of single-chip microcomputer (MCU), make the power supply design of card extender convenient, the LDO(linear voltage regulator of all size on the minimizing card extender) use also reduces cost, and has also realized the control of electrifying timing sequence.

Description of drawings

Fig. 1 is the power supply supply that provides of the utility model and the embodiment synoptic diagram of current sensing means;

Fig. 2 is the I that installs among the embodiment ²The mode that the articulates synoptic diagram of C bus;

Fig. 3 is the power supply supply option synoptic diagram that installs among the embodiment;

Fig. 4 is the circuit diagram of Fig. 3;

Fig. 5 is the working current testing circuit figure that installs among the embodiment;

Fig. 6 is the schematic internal view of chip MAX9611;

Fig. 7 is the standby current testing circuit figure that installs among the embodiment.

Embodiment

The design of native system is the control core with MEGA88PA, and control to module power supply and electrifying timing sequence is finished in the configuration of DAC LTC1669; Controllable electric power progressively increases (successively decreasing) with the 4.88mv stepping from 0-5V, and the electric current about maximum output 1.5A is enough to satisfy module to the requirement of power supply harshness.In the module course of work, pass through I ²C interface is in real time to the working current that reads to obtain module of the measured value of MAX9611; Under module PWDN situation, open DS2745 reads module with the precision of 1.5625uA standby current.MEGA88PA plays I simultaneously ²The effect that the C bus is isolated.

As shown in Figure 1, in the described power supply supply and the embodiment of current sensing means based on cell-phone camera module checkout equipment, the MCU(single-chip microcomputer) adopts MEGA88PA, also comprise 6 core assembly sheet DACLTC1669, pliotron D1760,6 core assembly sheet MAX9611, chip DS2745, described MEGA88PA is connected with chip DAC LTC1669, chip MAX9611, chip DS2745 respectively, described chip DAC LTC1669 is connected with the camera module by triode, and described chip MAX9611, chip DS2745 are connected with the camera module.

Be provided with I between described single-chip microcomputer MEGA88PA and camera module ²The C bus switch is for avoiding occurring under the unsuccessful situation of the frequent communication of I2C, by serious analysis and rational solution, with the next I at equipment of bus switch NC7SZ66 ²C bus and the I of system ²The C bus is isolated, at the switch of suitable situation by the I/0 control NC7SZ66 of MEGA88PA.

As shown in Figure 2, single-chip microcomputer MEGA88PA can avoid I ²The C conflict, single-chip microcomputer MEGA88PA has played I ²The effect that C isolates receives I by single-chip microcomputer MEGA88PA earlier ²Data on the C bus, the I by self simulating again ²The C bus communicates with devices such as MASTER mode and LTC1669, MAX9611, DS2745, has so just avoided I ²The problem of address conflict on the C bus.

As shown in Figure 3, adopt single-chip microcomputer MEGA88PA to control the DAC(digital to analog converter among the embodiment), what described DAC LTC1669 can be linear increases with the 4.88mv stepping in 0-5V, to satisfy the demand of camera module power supply.The band that adopts the voltage follow mode to improve DAC with amplifier LM2904 carries the isolation with voltage, protection DAC device.Realize the expansion of power supply is flowed with pliotron D1760, can realize the electric current output of maximum 1.5A, be enough to satisfy the demand of module power supply.This kind scheme implements simply, can get a desired effect.

Send order to single-chip microcomputer MEGA88PA by cell-phone camera module checkout equipment as required, single-chip microcomputer MEGA88PA sends its work that makes of ordering to working current detection module and standby current detection module again, working current detection means and standby current detection means will be read data again and pass to single-chip microcomputer, and cell-phone camera module checkout equipment passed to data again by single-chip microcomputer.

At the schematic diagram of this conceptual design as shown in Figure 4, because of the influence of the module of power supply Wen Bo very big, reasonable power filter network must be arranged on the network of the VCC_5V of key, VCC_12V when design circuit, and this could guarantee that just the voltage Wen Bo of output is in desirable scope.Because D1760 is for expanding the stream device, thermal value is many in the course of the work, need consider heat dissipation design when pcb board connects up.

Fig. 5 is the working current testing circuit figure that installs among the embodiment, the circuit diagram of described chip MAX9611, wherein points for attention as shown in Figure 6, the RS+ of described chip MAX9611, RS-directly are connected on sampling resistor two ends, there are special-purpose amplifier, the X1 that can select, X4 in inside, the X8 enlargement factor can select range to test the working current of module accurately flexibly.DAC also is at chip internal simultaneously, amplifies the signal of output like this and just can pass to ADC at chip internal, has reduced the interference of external signal, and the working current of test module can more meet design requirement.

Fig. 7 is the standby current testing circuit figure that installs among the embodiment, and adopting this kind mode to go to test module standby current main cause has following: 1. the module working current is very little generally all in the uA rank, so adopt discrete device to go test, is difficult to guarantee precision.If 2. separately test the standby current on each road power supply, very little of every electric current on the way is so adopt the way of test integrated testability, the current value that refluxes in the GND test.

Because the value of the minimum of DS2745 test is 1.5625uA, so can test the complete machine standby current of module very accurately.In actual test process, in the process of test P8V01C, the test result of using reometer as 90uA about, the value of using this frock to test is 87uA.Ce Shi result meets design requirement as can be seen.

Claims

1. power supply supply and current sensing means based on a cell-phone camera module checkout equipment, it is characterized in that: comprise single-chip microcomputer MEGA88PA, chip DAC LTC1669, triode, chip MAX9611, chip DS2745, described single-chip microcomputer MEGA88PA is connected with chip DACLTC1669, chip MAX9611, chip DS2745 respectively, described chip DAC LTC1669 is connected with the camera module by triode, described chip MAX9611, chip DS2745 are connected with the camera module, and described single-chip microcomputer MEGA88PA is connected with the camera module.

2. power supply supply and current sensing means based on cell-phone camera module checkout equipment according to claim 1, it is characterized in that: described chip DAC LTC1669 and chip MAX9611 are respectively 6 groups.

3. power supply supply and current sensing means based on cell-phone camera module checkout equipment according to claim 1 is characterized in that: be provided with I between described single-chip microcomputer MEGA88PA and camera module ²The C bus switch, described bus switch adopts chip NC7SZ66.

4. power supply supply and current sensing means based on cell-phone camera module checkout equipment according to claim 1 is characterized in that: be provided with amplifier chip LM2904 between described chip DAC LTC1669 and triode.

5. power supply supply and current sensing means based on cell-phone camera module checkout equipment according to claim 1, it is characterized in that: the RS+ pin of described chip MAX9611, RS-pin directly are connected on the two ends of sampling resistor, the inside of chip MAX9611 is provided with special-purpose amplifier, can select the enlargement factor of X1, X4, X8.

6. power supply supply and current sensing means based on cell-phone camera module checkout equipment according to claim 1 is characterized in that: described triode employing pliotron D1760.