Typical Application Circuit
RT9173/A
VCNTL= 3.3V
VIN = 2.5V
R1
2N7002
EN
R2
VIN VCNTL
RT9173/A
REFEN
VOUT
GND
CSS
CCNTL
CIN
COUT
RTT
RDUMMY
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
CSS = 1µF, CIN = 470µF (Low ESR), CCNTL = 47µF
Test Circuit
2.5V
3.3V
1.25V
VIN
VCNTL
REFEN RT9173/A VOUT
GND
VOUT
V
IL
COUT
Fig.1 Output Voltage Tolerance, ∆VOUT
2.5V
A
3.3V
1.25V
0.2V
VIN
VCNTL
REFEN RT9173/A VOUT
VOUT 1.25V
GND
0V
RL
V
COUT
RL and COUT
Time delay
Fig.2 Current in Shutdown Mode, ISHCLN
DS9173/A-06 March 2002
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