M52347FP 查看數據表（PDF） - Renesas Electronics

零件编号

产品描述 (功能)

生产厂家

M52347FP

SYNC SIGNAL PROCESSOR

Renesas Electronics 

M52347SP/FP

Application Method

1. Input Block

1) GREEN (SYNC ON VIDEO) IN (Pin 4)

Input with sync negative polarity.

Comparison of pin 4 input signal and the reference voltage of the inside of the IC performs the synchronous

separation. When the input at pin 4 is less than or equal to the reference voltage (2.8 V) and the flowing current is

more than or equal to the input sensitivity current (200 µA or more), the signal is separated.

When only a synchronous signal is input into pin 4, the operatable amplitude and the duty are as shown in Figure 1.

If the IC does not operate normally with the video signal input, change the value of external resistance R to make

the current optimum.

But, when capacity value is too big, output response becomes bad.

2) COMP/H IN, VIN (pins 6 and 8)

The composite sync input is connected to pin 6. H and V of the separate sync input are connected to pins 6 and 8,

respectively. For each of pins 6 and 8, the bias is 2.5 V and the impedance is 10 k. The internal double threshold

converter is used for shaping waveform and for detecting polarity.

Average DC voltage of input signal is 2.5 V. Each threshold voltage is set at a voltage 0.3 V away from this voltage.

If the duty ratio at pin 6 is small as shown in Figure 2, the optimum value is approx. 0.3 VP-P. If the duty ratio is

large, the optimum value is approx. 0.6 VP-P. Figure 3 shows the allowable input amplitude and the reference value

of duty test.

Only 5 V TTL input, decrease the amplitude by resistor splitting.

In addition, Figure 4 shows an example for improving the capability of the allowable duty when the input amplitude

is 0.7 VP-P or more.

To use the IC out of the standard value, remove the filter from pins 7 and 9, observe the waveform and check for a

match with the waveform shown in Figure 5.

30

25

R = 56 kΩ

20

15

R = 75 kΩ

10

5 f = 100 kHz

3.3 µ

4

R

0

0

0.2 0.4 0.6 0.8 1.0

Input Amplitude (VP-P)

Figure 1

Small POSI Duty

Large NEG Duty

Figure 2

≈ 2.8 V

≈ 2.5 V

≈ 2.2 V

Rev.2.00 Sep 14, 2006 page 10 of 16

Share Link: