THV3056 Datasheet, PDF (23/32 Pages) THine Electronics, Inc. – 3ch Buck/Boost 2ch CP 1ch HVLDO 1ch LVLDO Controller

THV3056_Rev.2.00_E
● Output Voltage Setting
Figure 13 shows ch-1 output voltage setting model. The voltage on INV1 pin is equal to the voltage on VREF pin due to
the effect of feed-back. The voltage on INV_1 pin is the divided voltage of Vout by R1 and R2.
So,
Vou
t1

-------^R---²--------
R1 + R2
=
VREF
Vout1
FB1
Therefore,
C1
Vout1
=
VRE
F



1
+
RR_----12_{-}
Since VREF =1.2V, then
R1
R3
R2
C2
Error AMP1
-
INV1 _{VREF +}
=1.2V
PWM Comparator
Vout1 = 1.2  _1 + ^RR----¹²-_
Similarly the output voltage of ch-2 and ch-3 is
described as follows.
C3
Vout2 = 0.85  _1 + ^RR----⁴⁵-_
Vout3 = 1.2  _1 + ^RR----⁷⁸-_
Vout2
FB2
R4
C4
R6
INV2
R5
Error AMP2
-
VREF ⁺
=0.85V
PWM Comparator
Vout3
FB3
C5
R7
C6
R9
ErrorAMP3
-
R8 ^INV3 VREF ⁺
=1.2V
PWM Comparator
Figure 13. Output Voltage Setting
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