THV3543 Datasheet, PDF (16/19 Pages) THine Electronics, Inc. – 2 channel Buck/Boost 2 channel Charge Pump Controller

THV3543_Rev.1.00_E
In VGL, the voltage on VGL_FB pin is controlled to be equal to zero (See Figure 8). The current through VGL_FB
pin can be ignored.
Thus,
VGL = −(VREF)× ^R6 = −1.2 × ^R6
R7
R7
VGL
R6
VGL_FB
R7
VREF
=1.2V
COMP
+
-
Output
Circuit
R6
R7
VGL
0V
Figure 8. VGL Output Voltage Setting
VREF
=1.2V
Output Voltage Setting (Fixed Mode)
When the output of CH-1 is connected directly to VO1-IN pin, the output voltage is in the fixed mode. Connect the
output of VGH and VGL directly to VGH_FB pin and VGL_FB pin respectively. CH-1, VGH and VHL are fixed at
15.6V, 35.6V and -6V respectively.
In CH-1, connect a capacitor for phase compensation between VO1_IN pin and INV1 pin, and also a resistance and a
capacitor between INV1 pin and FB1 pin (See Figure 9).
Vout1
VO1_IN
INV1
FB1
Error AMP1
-
VREF ⁺
=1.2V
PWM
Comp.
Figure 9. CH-1 Circuit in Fixed Output Voltage Mode
Copyright© 2011 THine Electronics, Inc.
16/19
THine Electronics, Inc.