915 Generation Operational Amplifier Single Op Amp Dual Op Amp TL071 TL072

Common single-op-amp and dual-op-amp Screening circuit boards, finished boards, the circuit board can whether the IC can be used for amplification, and can roughly the conversion rate of the chip.
IC1a in the circuit is connected to a multivibrator with a frequency of about 1Hz, and the OP Amp. to be tested is connected to a gain inverting amplifier working state. IC2 is an -OR gate, and table is that the output is 1 when the two inputs are inverted. The original design D3 is green, because the solder mask of the printed board is green and not eye-catching, so it is changed to a yellow LED.
For with a low conversion rate, the status indicated by the LED is steady yellow, and red will flicker faintly. This can also be used to roughly the conversion rate of the chip. Because most of the motorcycle on the market use low conversion rate of high rate, it can also be judged whether the chip is or not. Therefore, after power-on, there are the following situations:
If OP Amp. is normal, points A and B of IC2 must be reversed, so C is 1, and it is still 1 after IC1b and 1d, so D3 of the yellow LED lights up, and the red LED goes out
If the OP Amp. output is open, the C of IC2 must always be 0, and it will become 1 after IC1c, so that the yellow LED is extinguished and the red LED D4 is lit.
If the internal short circuit of OP Amp. makes the output voltage fixed to or negative, the output of IC1c is also a 1Hz low-frequency square wave, and the red and yellow will flash alternately.
The actual test of low conversion rate such as: OP07, LM741, yellow is always on, red is slightly .
Test with high conversion rates, such as TL071, NE5534, MC34071 and other , the yellow is always on, and the red is off.
Single op amp model: LM741, LF356, NE5534, TL071, TL081, OP07 and other standard package single op amp.
Dual op amp model: LM358, NE5532, TL072, TL082, MC1458, RC4558, OP275, AD827 and other standard package dual op amps.
PCB size: 9.2 x 5.8 cm
Power supply requirements: Voltage: 12VDC, current above 100mA.
Colour: black
Material: plastic Package Contents:
1 x Operational amplifier Only the above package content, other are not included.
Note: Light reflection and different displays may cause the color of the item in the a little different from the real . The measurement allowed error is +/- 1-3cm.