SI9105 Datasheet, PDF (1/7 Pages) Vishay Siliconix – 1-W High-Voltage Switchmode Regulator

Si9105
Vishay Siliconix
1-W High-Voltage Switchmode Regulator
FEATURES
D CCITT Compatible
D Current-Mode Control
D Low Power Consumption
(less than 5 mW)
D 10- to 120-V Input Range
D 200-V, 250-mA MOSFET
D Internal Start-Up Circuit
D Current-Mode Control
D SHUTDOWN and RESET
DESCRIPTION
The Si9105 high-voltage switchmode regulator is a monolithic
BiC/DMOS integrated circuit which contains most of the
components necessary to implement a high-efficiency dc/dc
converter in ISDN terminals up to 3 watts. A 0.5-mA max
supply current makes possible the design of a dc/dc converter
with 60% efficiency at 25 mW, therefore meeting the
recommended performance under the CCITT
I.430 specifications.
This device may be used with an appropriate transformer to
implement isolated flyback power converter topologies to
provide single or multiple regulated dc outputs (i.e., "5 V).
The Si9105 is available in both standard and lead (Pb)-free
16-pin wide-body SOIC, 14-pin plastic DIP and 20-pin PLCC
packages which are specified to operate over the industrial
temperature range of −40_C to 85_C.
FUNCTIONAL BLOCK DIAGRAM
V_REF
BIAS
V_CC
+V_IN
OSC OSC
FB
COMP DISCHARGE
IN OUT
Error
Amplifier
−
+
4 V (1%)
Ref
Gen
2V
−
+
+
−
1.2 V
Current-Mode
Comparator
OSC
Clock (½ f_OSC)
R
Q
S
C/L
Comparator
Current
To
Sources
Internal
Circuits
V_CC
8.7 V
Undervoltage Comparator
−
+
−
+
9.3 V
S
Q
R
DRAIN
−V_IN
(BODY)
SOURCE
SHUTDOWN
RESET
Document Number: 70003
S-42030—Rev. H, 15-Nov-04
www.vishay.com
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