1996 Oct 25

17

Philips Semiconductors

Product specification

Video processor with automatic cut-off

and white level control

TDA4680

Notes to the characteristics

1. The values of the

−(B − Y) and −(R − Y) colour difference input signals are for a 75% colour-bar signal.

2. The pins are capacitively coupled to a low ohmic source, with a recommended maximum output impedance of 600

Ω.

3. The white potentiometers affect the amplitudes of the RGB output signals including the white measurement pulses.

4. The RGB outputs at pins 24, 22 and 20 are emitter followers with current sources.

separate the components of the sandcastle pulse. The particular component is generated when the voltage on pin 14

exceeds the defined internal threshold voltage.

The internal threshold voltages (control bit SC5 = 0) are:

1.5 V for horizontal and vertical blanking pulses

3.5 V for horizontal pulses

6.0 V for the burst key pulse.

The internal threshold voltages (control bit SC5 = 1) are:

1.5 V for horizontal and vertical blanking pulses

3.5 V for the burst key pulse.

7. Average beam current limiting reduces the contrast, at minimum contrast it reduces the brightness.

8. Peak drive limiting reduces the RGB outputs by reducing the contrast, at minimum contrast it reduces the brightness.

the maximum voltage, peak drive limiting is delayed by one horizontal line.

input frequency range

0

−

100

kHz

LOW level input voltage

−−

1.5

V

HIGH level input voltage

3.0

−

6.0

V

LOW level input current

−10

−−

µA

HIGH level input current

−−

10

µA

clock pulse LOW

4.7

−−

µs

clock pulse HIGH

4.0

−−

µs

rise time

−−

1.0

µs

fall time

−−

0.3

µs

LOW level input voltage

−−

1.5

V

HIGH level input voltage

3.0

−

6.0

V

LOW level input current

−10

−−

µA

HIGH level input current

−−

10

µA

LOW level output current

3.0

−−

mA

rise time

−−

1.0

µs

fall time

−−

0.3

µs

data set-up time

0.25

−−

µs

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT