Philips DVDR725H, Руководство по обслуживанию

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Circuit-, IC descriptions and list of abbreviations
EN 180 HDRW720/0x, DVDR725H/0x 9.
9.10.3ICs Digital Board Chrysalis
IC7106 NCP303LSN29, Digital Board 2.1 Chrysalis, Reset Circuit
IC7501 NCP1570D, Digital Board 2.1 Chrysalis, DC/DC Converter Control
NCP303LSNxxT1
Open Drain Output Configuration
V
ref
2 Input
3 Gnd 5 C
D
R
D
1 Reset Output
NCP1570
Figure 2. Block Diagram
–
+
UVLO COMP
–
+
–
+
–
+
Fault Latch
Set Dominant
+
–
0.25 V
Error Amp
–
R
S
Q
PWM Latch
Reset Dominant
PWM COMP
+
Σ
OSC
Art Ramp
80%, 200 kHz
0.525 V
+
–
8.5 V/7.5 V
+
–
0.985 V
S
R
Q
V
CC
GND
V
FB
COMP
GATE(H)
GATE(L)
PGDELAY
PWRGD
Non
Overlap
V
CC
+
–
0.89 V/0.69 V
+
–
+
–
0.25 V
S
R
Q
PGDELAY Latch
Set Dominant
–
+
+
–
3.3 V
12
µ
A
+
–