SI786 Datasheet, PDF (10/14 Pages) Vishay Siliconix – Dual-Output Power-Supply Controller

Si786
Vishay Siliconix
SCHEMATIC DRAWINGS
INPUT
5.5 V to 30 V
C1
22 mF
D2A
1N4148
3.3 V
at 3 A
C7
150 mF
R1
25 mW
N1
L1
10 mH
C5
0.1 mF
D1
D1FS4
N3
C12
150 mF
(Note 1)
3.3 V ON/OFF
5 V ON/OFF
SHUTDOWN
C9
0.01 mF
OSC SYNC
Note 1: Use short, Kelvin-connected
PC board traces placed very
close to one another.
100 W
0.1 mF
Si786
23
V+
25 _BST3
27
DH₃
26 _LX3
V_L ²²
BST₅ ¹⁸
16
DH₅
LX₅ ¹⁷
24 _DL3
DL₅ ¹⁹
1 _CS3
28 _FB3
2 _SS3
3 _ON3
13
ON₅
12
SHDN
11 _SYNC
9 _GND
10
REF
CS₅ ¹⁵
FB₅ ²¹
SS₅ ¹⁴
6
V_H
4
D₁
8
Q₁
D₂ ⁵
Q₂ ⁷
20
PGND
C3
1 mF
D2B
1N4148
C4
0.1 mF
C10
22 mF
5 V at 5 mA
10 mF
N2
L2
10 mH
R2
25 mW
5 V at
3A
N3
D1
D1FS4
C6
330 mF
(Note 1)
C8
0.01 mF
COMPARATOR SUPPLY INPUT
IN _{COMPARATOR 1}
OUT
IN _{COMPARATOR 2}
OUT
3.3 V at 5 mA
V+
V_L
REF
SHDN
FIGURE 1. Si786 Application Circuit
5-V LDO
Linear
Regulator
3.3-V
Reference
ON
4.5 V
3.3-V
PWM
Controller
(See Figure 3)
ON
4V
SYNC
2.8 V
300 kHz/200 kHz
Oscillator
ON
STANDBY
5-V
PWM
Controller
(See Figure 3)
ON
FB₃
CS₃
BST₃
DH₃
LX₃
DL₃
SS₃
PGND
ON₃
FB₅
CS₅
BST₅
DH₅
LX₅
DL₅
SS₅
www.vishay.com
10
D₁
1.65 V
D₂
1.65 V
FIGURE 2. Si786 Block Diagram
ON₅
V_H
Q₁
Q₂
Document Number: 70189
S-40807—Rev. J, 26-Apr-04