Vcc1

2

To frame amplifier

Frame

sync pulse

INPUT CURRENT

COMPENSATION

Figure 6 : Frame Oscillator

Vcc1

18

19

14

Line

Flyback

Input

Vcc1

RC

SSC

Output

RC

Network

Σ

Line

Flyback

Detection

Burst gate

pulse

generator

8

Frame

Blanking

Generator

Vcc1

R

C

BurstKey

Figure 7 : Super sandcastle generator

Line output (Pin 17)

It is an open-collector output. The output positive

pulse time is 28

µs for a 64µs period. The oscillator

thresholds are internally fixed by resistors. The

oscillator is synchronized during the last half free

run period. The input current during the charge of

the capacitor is less than 100nA.

Frame output amplifier

This amplifier is able to drive directly the frame

yoke. Its output is short circuit and overload pro-

tected; it contains also a thermal protection.

The line flyback detection is provided by a compa-

rator which compares the input line flyback pulse

to an internal reference. The burst gate pulse posi-

tion is fixed by the external RC network (pin 14). It

is referenced to the middle of the line flyback.

The frame blanking generator is a monostable with

external R.C. The start blanking pulse is triggered

by the falling edge of the frame saw-tooth (Pin 2).

The reset is provided by a comparator which com-

pares the capacitor voltage during its charge to an

internal threshold fixed by resistors.

The frame blanking time is defined by :

⋅ R.C.

This pulse is available on Super Sand Castle output

(Pin 19).

Remark : For compatability with TEA5640, frame

blanking time must be larger than 1.15ms with

centered value @ 1.35ms (R = 100k

Ω ± 1%,

C = 22nF

± 5%)

TDA8218

7/9