TDA8385 Datasheet, PDF (3/21 Pages) NXP Semiconductors – Control circuit for a Self-Oscillating Power Supply SOPS

Philips Semiconductors
Control circuit for a Self-Oscillating
Power Supply (SOPS)
Preliminary specification
TDA8385
handbook, full pagewidth
stand-by voltage input
Vsb ₁₀
latch
2.5 V
2V
25
2.5 V
STAND-BY IX
Vr
Vsim
PWM
8
IV
comparator
TDA8385
latch
OUTPUT
LED
STAGE
15
2
LED driver output
17
LED DRIVER VI
Q (23)
18
(28)
26
100 mV ₁₀
S
FF Q
R
13
14
16
demagnetization
LED CONTROL V
demagnetization
Vc
DELAY
12
I _sim
I12
12
0.2 I12
9
5
I _peak
DEM
15
11
115 mV
6
SAWTOOTH GENERATOR
II
current simulation
input
peak-current
setting input
demagnetization
input
delay setting
March 1994
(17)
100 µA
slow
discharge
21
OVER-VOLTAGE PROTECTION
Q
R
FF
23
Q
S
(28)
24
115 mV
over voltage
8
over-voltage
22
protection
2.5 V
VIII
MCD418
Fig.2 Block diagram; part B (continued from Fig.1; part A).
4