RT9173B
Typical Application Circuit
V
= 3.3V
CNTL
V
= 2.5V
IN
R
C
TT
CNTL
C
R
IN
VCNTL
VIN
1
RT9173B
REFEN
VOUT
2N7002
EN
GND
R
2
C
OUT
R
DUMMY
R1 = R2 = 100kΩ, RTT = 50Ω / 33Ω / 25Ω
COUT(MIN) = 10μF (Ceramic) + 1000μF under the worst case testing condition
RDUMMY = 1kΩ as for VOUT discharge when VIN is not present but VCNTL is present
CIN = 470μF (Low ESR), CCNTL = 47μF
Test Circuit
3.3V
2.5V
VCNTL
VIN
RT9173B
REFEN
V
OUT
C
1.25V
VOUT
V
GND
OUT
I
L
Figure 1. Output Voltage Tolerance, ΔVOUT
3.3V
2.5V
A
VCNTL
RT9173B
REFEN
VIN
1.25V
V
OUT
C
1.25V
0.2V
VOUT
0V
GND
OUT
R
L
V
R and C
L
OUT
Time deleay
Figure 2. Current in Shutdown Mode, ΙSHDN
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DS9173B-09 March 2007
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
