How to judge the pin order of ic chip

The way to identify the pins of digital IC is to align the letters and codes on the front of the IC with the positioning mark facing to the left, then the pin on the lower left is 1 pin, then count the pins counterclockwise, that is, the second pin, the third pin, and so on.

The pin order of some imported IC circuits is reversed. The model of this type of integrated circuit is followed by the suffix letter "R". The model without "R" is a straight pin, and the model with "R" is a reverse pin;

For example: M5 1 15 and M51/5rp, HA 1339A and HA 1339AR, HA 1366W and ha/kloc-0. Attention should be paid to identifying the pin number of this IC.

function

Pin (1) is a multifunctional pin, through which the internal FM demodulation circuit can demodulate the second audio IF signals in various formats in an unbalanced manner. At the same time, it is also the control pin of AV\TV conversion and PAL, NTSC and SECAM color system conversion in the block, and the input impedance is about 3.4K.

(2) This pin is an identification output pin, which outputs an image identification signal in a C-gate mode. When the TV mode has received the image TV signal, this pin presents high impedance to the outside, and a pull-up resistor can be connected externally to obtain a high-level signal; When no signal is received, the pin presents low impedance and outputs low level.

Above content reference: Baidu Encyclopedia -Pin