SI9114A Datasheet, PDF (1/5 Pages) Vishay Siliconix – High-Frequency Switchmode Controller

Si9114A
Vishay Siliconix
High-Frequency Switchmode Controller
FEATURES
D 15- to 200-V Input Range
D Current-Mode Control
D Internal Start-Up Circuit
D Latched SHUTDOWN
D Soft-Start
D 1.8-MHz Error Amp
DESCRIPTION
The Si9114A is a BiC/DMOS current-mode pulse width
modulation (PWM) controller IC for high-frequency dc/dc
converters. Single-ended topologies (forward and flyback) can
be implemented at frequencies up to 1 MHz. The oscillator has
an internal divide-by-two that limits the duty ratio to 50%. An
oscillator sync output allows converters to be synchronized in
phase as well as in frequency, in a master/slave configuration.
The output inverter can typically source 500 mA and sink
700 mA. Shoot-through current is all but eliminated to minimize
supply current requirements.
The high-voltage DMOS transistor allows the IC to interface
directly to bus voltages up to 200 V. Other features include a
1.5% accurate voltage reference, 1.8-MHz (min) bandwidth
error amplifier, shutdown logic control, soft-start and
undervoltage lockout circuits.
The Si9114A is available in both standard and lead (Pb)-free
14-pin plastic DIP and SOIC packages, and is specified over
the industrial, D suffix (−40_C to 85_C) temperature range.
FUNCTIONAL BLOCK DIAGRAM
4
NI
CURRENT
FB COMPENSATION SENSE
5
6
13
Error
Amplifier
−
+
3
V_REF
Ref
Gen
2V
+− ^−
+
7
SS
4.6 V
20 mA
+
−
1.25 V
−V_IN
14
V_CC
1
+V_IN
−
−
0.2 V
+
+
9.2 V
SYNC
10
R_OSC C_OSC
8
9
OSC
Out
B2
OSC
Enable
R
Q
S
V_CC
Substrate
20 mA
S
Q
R
−
+
Undervoltage
Lockout
12 _DRIVER
OUTPUT
11
−V_IN
2
SHUTDOWN
Document Number: 70025
S-42044—Rev. E, 15-Nov-04
www.vishay.com
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