1996 Jun 17

13

Philips Semiconductors

Preliminary specification

YUV picture improvement processor based

on histogram modification and blue stretch

TDA9171

TEST AND APPLICATION INFORMATION

The TDA9171 is especially designed for YUV applications. A typical application diagram is shown in Fig.8. Jumpers

J1 and J2 can be used to select the appropriate luminance amplitude mode. Potentiometers BLG, BLM and NLC can be

used to apply proper blue stretch and non-linear amplifier control voltages.

The TDA9171 is also prepared for YC-processing. A typical application diagram is shown in Fig.9. Jumpers J1 and J2

can be used to select the appropriate luminance amplitude mode. Potentiometer NLC can be used to apply the proper

non-linear amplifier control voltage. For the chroma processing either the U- or V-channel can be used, however both

channels need to be DC-decoupled and the DC-decoupling capacitor value should be such that the burst period of the

switched off by connecting both blue stretch adjustments (BLG and BLG) to ground.

Fig.8 YUV application.

handbook, full pagewidth

TDA9171

MGD298

1

2

3

UIN

UOUT

VOUT

YOUT

GND

VCC

VIN

YIN

J1

J2

SC

4

5

6

7

8

9

10

20

BLM

BLG

19

18

17

16

15

14

13

12

10 nF

100 nF

100 nF

10 nF

10 nF

11

220 nF

10 nF

10 nF

100 nF

10 nF

10 nF

220 k

Ω

470 k

Ω

470 k

Ω

470 k

Ω

180 k

Ω