Flashlight function test module

Abstract

The utility model provides a flash lamp function test module. The circuit comprises a constant current source circuit, the constant current source circuit comprises a potentiometer voltage division circuit, a differential amplifier, a first operational amplifier, a second operational amplifier and a sampling resistor which are connected in sequence, the input end of the potentiometer voltage division circuit is connected with 3.3 V voltage, and a pin 6 of the differential amplifier is used for current output. The in-phase input end of the second operational amplifier and one end of the sampling resistor are both connected with the constant current output end of the constant current source circuit, the constant current output end is connected into the single-chip microcomputer and supplies power to the flash lamp, and the single-chip microcomputer is connected with a flash lamp color detection circuit. The utility model relates to the field of electronic device testing.

Description

Technical Field

[0001] This utility model relates to the field of electronic device testing, and in particular to a flash lamp function testing module. Background Technology

[0002] In flash unit functional testing, the traditional method is to power the flash unit through a light source controller and use a flash unit tester to measure the flash unit's brightness, color temperature, duration, recycle time, uniformity, etc. Among these methods, the light source controller and flash unit tester are expensive and bulky. In addition, current technology cannot measure the forward conduction voltage of the flash unit and the values ​​of red, green, blue, and white light when it is lit.

[0003] Therefore, it is essential to develop a high-precision, stable, and low-cost flash lamp function test circuit. Utility Model Content

[0004] In view of the problems existing in the prior art, this utility model proposes a flash lamp function test circuit with high precision, good stability and low cost.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: a flash lamp function test module, including a constant current source circuit. The constant current source circuit includes a potentiometer voltage divider circuit, a first operational amplifier, a differential amplifier, a second operational amplifier, and a sampling resistor connected in sequence. The input terminal of the potentiometer voltage divider circuit is connected to a 3.3V voltage, and the output terminal of the potentiometer voltage divider circuit is connected to the non-inverting input terminal of the first operational amplifier. The output terminal and the inverting input terminal of the first operational amplifier are both connected to pin 3 of the differential amplifier, and pin 6 of the differential amplifier is used for current output. The output and inverting input of the second operational amplifier are connected to pin 1 of the differential amplifier. The non-inverting input of the second operational amplifier and one end of the sampling resistor are both connected to the constant current output of the constant current source circuit. The constant current output is connected to a microcontroller and supplies power to the flash lamp. The microcontroller is connected to a flash lamp color detection circuit. An NMOS transistor is placed between pin 6 of the differential amplifier and the constant current output. The gate of the NMOS transistor is connected to pin 6 of the differential amplifier, the drain is connected to a 12V voltage, and the source is connected to the other end of the sampling resistor.

[0006] Based on the above, a circuit is built using a differential amplifier to input a 3.3V voltage and control the output of a constant current source from 0 to 1.1A. This constant current output powers the flash lamp, and the flash lamp color detection circuit L3 reads the red, green, blue, and white light values ​​of the flash lamp. The differential amplifier internally includes a laser-trimmed matching resistor, ensuring accurate and stable gain, thereby improving the accuracy and stability of the entire constant current source circuit. The potentiometer voltage divider circuit is used to adjust the circuit voltage and is connected to the first operational amplifier. Utilizing the infinite input impedance of the first operational amplifier, the voltage after voltage division is avoided by subsequent circuits. The first operational amplifier inputs the maximum reference voltage to pin 3 of the differential amplifier, and the second operational amplifier inputs the feedback voltage to pin 1 of the differential amplifier. The differential amplifier compares the reference voltage and the feedback voltage. After comparison, the output of the differential amplifier is adjusted to maintain the balance between the reference voltage and the feedback voltage. The output of the self-test constant current source is read by the voltage drop across the sampling resistor. The NMOS transistor is driven through pin 6 of the differential amplifier to provide the required high current output.

[0007] Furthermore, the potentiometer voltage divider circuit includes a fourth resistor, a fifth resistor, a seventh resistor, an eighth capacitor, and a potentiometer. One end of the fourth resistor is connected to a 3.3V voltage, and the other end is connected to the potentiometer's interface 1. One end of the seventh resistor is connected to the potentiometer's interface 3, and the other end is grounded with one end of the eighth capacitor. The other end of the eighth capacitor is connected to the potentiometer's sliding contact 2. One end of the fifth resistor is connected to the potentiometer's sliding contact 2, and the other end is connected to the non-inverting input terminal of the differential amplifier.

[0008] Based on the above, the output voltage of the potentiometer voltage divider circuit is adjusted by the potentiometer to control the output voltage from 0 to 0.66V.

[0009] Furthermore, the flash color detection circuit includes a color sensor, a first resistor, and a second resistor. Pin 1 of the color sensor is grounded, pin 2 is connected to one end of the second resistor, and pin 3 is connected to one end of the first resistor. The first resistor, the second resistor, and pin 4 of the color sensor are all connected to a voltage input terminal, which is equipped with a low-dropout linear regulator.

[0010] Based on the above, the color sensor integrates photodiodes, which convert received light signals into electrical signals. When light shines on the photodiode, photons interact with the semiconductor material, generating electron-hole pairs, which in turn form an electric current. Since the weak electrical signal generated by the photodiode is amplified to make it easier for subsequent circuits to process, the amplified analog electrical signal needs to be converted into a digital signal, which is then processed by the microcontroller via I / O. 2 The C-communication reads the digital signal data from the color sensor and performs further processing as needed to obtain the red, green, blue, and white light values ​​when the flash is on.

[0011] Furthermore, the 3.3V voltage connected to the constant current source circuit is provided by a relay control circuit, which includes a signal relay, a general-purpose diode, a light-emitting diode, and an eleventh resistor. The input terminal of the general-purpose diode and the output terminal of the light-emitting diode are both connected to the interface 8 of the signal relay. The output terminal of the general-purpose diode and one end of the eleventh resistor are both connected to the interface 1 of the signal relay, and the other end of the eleventh resistor is connected to the input terminal of the light-emitting diode.

[0012] To more clearly illustrate the above-mentioned features of this utility model and the objectives it aims to achieve, the present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0013] Figure 1 : This is the circuit schematic of a constant current source circuit;

[0014] Figure 2 : This is the circuit diagram of the flash color detection circuit;

[0015] Figure 3 : This is the circuit diagram of a relay control circuit;

[0016] Figure 4 : This is a connection diagram for microcontroller interface 1;

[0017] Figure 5 : This is a connection diagram for microcontroller interface 2. Detailed Implementation

[0018] like Figure 1As shown, a flash lamp function test module includes a constant current source circuit L1. The constant current source circuit L1 includes a potentiometer voltage divider circuit L2, a first operational amplifier U3B, a differential amplifier U2, a second operational amplifier U3A, and a sampling resistor connected in sequence. The input terminal of the potentiometer voltage divider circuit L2 is connected to a 3.3V voltage. The output terminal of the potentiometer voltage divider circuit L2 is connected to the non-inverting input terminal of the first operational amplifier U3B. The output terminal and the inverting input terminal of the first operational amplifier U3B are both connected to pin 3 of the differential amplifier U2. Pin 6 of the differential amplifier U2 is used for current output. The output terminal and the inverting input terminal of the second operational amplifier U3A are connected to pin 1 of the differential amplifier U2. The non-inverting input terminal of the second operational amplifier U3A and one end of the sampling resistor R6 are both connected to the constant current output terminal I_OUT of the constant current source circuit L1. The constant current output terminal I_OUT is connected to a microcontroller and supplies power to the flash lamp. The microcontroller is connected to a flash lamp color detection circuit L3.

[0019] Preferably, an NMOS transistor Q1 is provided between pin 6 of the differential amplifier U2 and the constant current output terminal I_OUT. The gate G of the NMOS transistor Q1 is connected to pin 6 of the differential amplifier U2, the drain D is connected to a 12V voltage, and the source S is connected to the other end of the sampling resistor R6.

[0020] Preferably, the potentiometer voltage divider circuit L2 includes a fourth resistor R4, a fifth resistor R5, a seventh resistor R7, an eighth capacitor C8, and a potentiometer RP1. One end of the fourth resistor R4 is connected to a 3.3V voltage, and the other end is connected to interface 1 of the potentiometer RP1. One end of the seventh resistor R7 is connected to interface 3 of the potentiometer RP1, and the other end is grounded with one end of the eighth capacitor C8. The other end of the eighth capacitor C8 is connected to the sliding contact 2 of the potentiometer RP1. One end of the fifth resistor R5 is connected to the sliding contact 2 of the potentiometer RP1, and the other end is connected to the non-inverting input terminal of the differential amplifier U2.

[0021] Preferably, the flash color detection circuit L3 includes a color sensor U1, a first resistor R1, and a second resistor R2. Pin 1 of the color sensor U1 is grounded, pin 2 is connected to one end of the second resistor R2, and pin 3 is connected to one end of the first resistor R1. The first resistor R1, the second resistor R2, and pin 4 of the color sensor U1 are connected to a voltage input terminal, which is equipped with a low dropout linear regulator LDO.

[0022] Preferably, the 3.3V voltage connected to the constant current source circuit L1 is provided by the relay control circuit L4. The relay control circuit L4 includes a signal relay K3, a general-purpose diode D11, a light-emitting diode LED1, and an eleventh resistor R11. The input terminal of the general-purpose diode D11 and the output terminal of the light-emitting diode LED1 are both connected to the interface 8 of the signal relay K3. The output terminal of the general-purpose diode D11 and one end of the eleventh resistor R11 are both connected to the interface 1 of the signal relay K3. The other end of the eleventh resistor R11 is connected to the input terminal of the light-emitting diode LED1.

[0023] The specific implementation method of this embodiment is as follows:

[0024] 1. Turn on the signal relay K3, adjust the potentiometer RP1 and measure the voltage across the sampling resistor R6 to reach 600mV, ensuring the constant current source output I. f =1A±5mA.

[0025] 2. Turn off the signal relay K3, and bring out the positive and negative terminals of the flash chip to be tested through the probes and connect them to the constant current output terminal I_OUT.

[0026] 3. Connect the positive and negative terminals of the flash chip to be tested in parallel to the electrical testing system V9.

[0027] 4. Turn on the signal relay K3 and use the electrical testing system V9 to measure the forward conduction voltage drop V of the flash lamp. f 3-4V.

[0028] 5. Place the color sensor U1 and the flash in a completely dark environment, and add a light attenuation device between the color sensor U1 and the flash to prevent the color sensor U1 reading from exceeding the upper limit of the sensor's readable value. Use a microcontroller to control the reading via I... 2 In the C communication mode, the red, green, blue and white light values ​​read from the color sensor U1 are used to take the median value of 500 data points ±30% as a threshold to block blue light leakage caused by faulty lamps or damaged phosphors.

[0029] 6. Turn off signal relay K3, and use a microcontroller to connect via I... 2 In the C communication mode, if all the red, green, blue, and white light values ​​read from the color sensor U1 are 0, it is considered a failure.

[0030] The above description is only the optimal solution embodiment of this utility model and is not intended to limit this utility model. Various modifications or substitutions made by those skilled in the art to this utility model without departing from the essence and protection scope of this utility model should also be within the protection scope of this utility model.

Claims

1. A flash function testing module, characterized in that: The circuit includes a constant current source circuit (L1), which comprises a potentiometer voltage divider circuit (L2), a first operational amplifier (U3B), a differential amplifier (U2), a second operational amplifier (U3A), and a sampling resistor (R6) connected in sequence. The input of the potentiometer voltage divider circuit (L2) is connected to a 3.3V voltage. The output of the potentiometer voltage divider circuit (L2) is connected to the non-inverting input of the first operational amplifier (U3B). The output and inverting input of the first operational amplifier (U3B) are both connected to pin 3 of the differential amplifier (U2). Pin 6 of the differential amplifier (U2) is used for current output. The output and inverting input of the second operational amplifier (U3A) are connected to the sampling resistor (R6). Pin 1 of the differential amplifier (U2) is connected. The non-inverting input of the second operational amplifier (U3A) and one end of the sampling resistor (R6) are both connected to the constant current output (I_OUT) of the constant current source circuit (L1). The constant current output (I_OUT) is connected to a microcontroller and supplies power to the flash. The microcontroller is connected to a flash color detection circuit (L3). An NMOS transistor (Q1) is placed between pin 6 of the differential amplifier (U2) and the constant current output (I_OUT). The gate (G) of the NMOS transistor (Q1) is connected to pin 6 of the differential amplifier (U2), the drain (D) is connected to a 12V voltage, and the source (S) is connected to the other end of the sampling resistor (R6).

2. The flash function testing module according to claim 1, characterized in that: The potentiometer voltage divider circuit (L2) includes a fourth resistor (R4), a fifth resistor (R5), a seventh resistor (R7), an eighth capacitor (C8), and a potentiometer (RP1). One end of the fourth resistor (R4) is connected to a 3.3V voltage, and the other end is connected to interface 1 of the potentiometer (RP1). One end of the seventh resistor (R7) is connected to interface 3 of the potentiometer (RP1), and the other end is grounded to one end of the eighth capacitor (C8). The other end of the eighth capacitor (C8) is connected to the sliding contact 2 of the potentiometer (RP1). One end of the fifth resistor (R5) is connected to the sliding contact 2 of the potentiometer (RP1), and the other end is connected to the non-inverting input terminal of the differential amplifier (U2).

3. The flash function testing module according to claim 1, characterized in that: The flash color detection circuit (L3) includes a color sensor (U1), a first resistor (R1) and a second resistor (R2). Pin 1 of the color sensor (U1) is grounded, pin 2 is connected to one end of the second resistor (R2), and pin 3 is connected to one end of the first resistor (R1). Pin 4 of the first resistor (R1), the second resistor (R2), and the color sensor (U1) are all connected to a voltage input terminal, which is equipped with a low dropout linear regulator (LDO).

4. The flash function testing module according to claim 1, characterized in that: The 3.3V voltage connected to the constant current source circuit (L1) is provided by the relay control circuit (L4). The relay control circuit (L4) includes a signal relay (K3), a general-purpose diode (D11), a light-emitting diode (LED1), and an eleventh resistor (R11). The input terminal of the general-purpose diode (D11) and the output terminal of the light-emitting diode (LED1) are both connected to the interface 8 of the signal relay (K3). The output terminal of the general-purpose diode (D11) and one end of the eleventh resistor (R11) are both connected to the interface 1 of the signal relay (K3). The other end of the eleventh resistor (R11) is connected to the input terminal of the light-emitting diode (LED1).

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