DEFINITION OF MODE SWITCHING

Status

Pin 2

Pin 4

Function

A

Not connected

No External Voltage

Standard B/G mode, gated charge and discharge.

B

12V

HIgh Impedance

No External Voltage

Standard B/G, ungated, charging up to sync. level, discharging

dependant from average signal (peri operation).

C

12V

Low Impedance

No External Voltage

At standard L ungated, charging up to peak white level,

discharge dependant from average signal level, inverted polarity

of the video output.

D

No specifications

≥ 7.5V

In VTR reading mode the IF amplifier is blocked, turned gain

controlled down : the video output signal is fixed at constant ultra

white level for standard B/G mode.

The gating pulse at Pin 7 is internally switched off.

STATUS OF MODE SWITCHING, REFERRING TO CONTROL VOLTAGE PIN 2

Control Voltage

Pin 2

Connections of

Pin 2

Status

Function

1.2 to 2.5V*

Open

A

Standard B/G gated sync. operation

3.0 to 5.0V

High Impedance

B

Standard B/G, no sync., operation

> 6.5V

Low Impedance

C

Standard L

0.0 to 0.8V

Ground

D

Standard L

* Voltage measured on Pin 2.

3

2

1

0

04

8

12

V2 (V)

I2 (nA)

TDA4443

I2

+12V

V2

V2

DA

B

C

STATUS

0.8

1.2

2.5

3.0

5.0 6.5

TDA4443

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