71128 Datasheet, PDF (6/7 Pages) Vishay Siliconix – Simple Solution for Dynamically Programming the Output Voltage of DC-DC Converters

AN731
Vishay Siliconix
P1
1
V_IN
2.7 – 6 V*
P2
1
GND
JP1
1
2PWM
-PSM
3
TP2
1
GND
C9
1 mF
JP2
1
2 ^Enable
Disable
3
TP3
SYNC
+1.3 V
C3
1 mF
U1
1 _VS
2 _NC
MODE ¹⁶
SD ¹⁵
3 _DL
D_L ¹⁴
4 _{PWM/PSM PGND} 13
5 _SYNC
6 _GND
7 _VREF
V_OUT ¹²
V_DD ¹¹
R_OSC ¹⁰
8 _FB
COMP ⁹
Si9166
C7
100 pF
C1
6, 7 _{0.1 mF}
R7*
50 W
Q1A
Si6801DQ
4
Q1B
Si6801DQ
L1
8
1
1.5 mH
IHLP2525
2, 3
R6
3.9 kW
R5
25 kW
C8
1000 pF
C6
0.1 mF
C4
10 mF
C2
10 mF
P3
V_OUT
1
R1
100 W
0.4 – 3.4 V
1.2 A
Adjustable
TP1
R2
22.1 kW
R3
2 kW
C5
220 pF
P5
V_A
0.2 – 2.7 V
1
R8, 22.1 kW
R9, 390 W
V_IN
R11
3.60 kW
2
U2A
-
1
3₊
LM358D
R10
10 kW
R4
3.01 kW
Vx
P4
1
PGND
6
U2B
-
7
5
+
LM358D
C10
0.1 mF
JP1: PWM/–PSM to V_IN for PWM mode;
PWM/–PSM to PGND for PSM mode.
JP2: –SD to V_IN for converter enable mode;
–SD to PGND for shutdown mode.
NOTE: V_IN must be > V_OUT +0.6 V for output regulation
* = Optional
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6
FIGURE 6. Example Circuit Using Si9166 Controller
Document Number: 71128
28-Jan-00