POWER CMOS DRIVERS WITH VOLTAGE TRIPLER
TC4626
TC4627
BOOSTER FUNCTION
The voltage booster is an unregulated voltage tripler
circuit. The tripler consists of three sets of internal switches
and three external capacitors. S1a and S1b charge capaci-
tor C1 to V
DD
potential. S2a and S2b add C1 potential to V
DD
input to charge C2 to 2 x V
DD
. S3a and S3b add C1 potential
to C2 to charge C3 to 3 x V
DD
. The position of the switches
is controlled by the internal 4 phase clock.
Pin 1 & 2 Waveforms
3 x VDD
1
2
3
4
PIN 2
VOLTAGE
2 x VDD
VDD
2 x VDD
6
C3
3 x VDD, VBOOST
6
PIN 1
VOLTAGE
VDD
0
S3a
3
C2
2 x VDD
S2a
S3b
(4 To 6V)
VDD
8
S1a
2
S2b
ON
S1
OFF
C1
1
S1b
GND
4
S2
ON
OFF
S3
ON
OFF
5
Position of Switches
Voltage Booster
6
7
8
TELCOM SEMICONDUCTOR, INC.
4-275
TELCOM [ TELCOM SEMICONDUCTOR, INC ]
