Preliminary
RT9177
Ultra-Low-Noise 200mA LDO Regulator
General Description
The RT9177 is a 200mA low dropout and low noise
micro-power regulator suitable for portable RF
applications. The output voltage accuracy within
±2%
and range from 2.4V to 3.2V in 100mV
increments could be selected. It is designed for
using very low ESR output capacitor. Its output
remains stable even in using 1µF ceramic as its
output capacitor.
Using an internal PMOS as the pass device cause
that don’t need extra GND current in heavy load and
dropout conditions. In shutdown mode, nearly zero
operation current cause the IC is suitable for
battery-power devices. Other features including
current limiting, over temperature protection and
adding a capacitor in bypass pin to improve its noise
performance are functional.
Features
Ultra-Low-Noise(150nV/
Hz
) for RF Application
1µF Ceramic C
OUT
Stable
µ
Low Dropout Voltage(220mV @ 200mA)
Low Operation Current - 80µA Typical
µ
Shutdown Function
Low Temperature Coefficient
Current and Thermal Limiting
Custom Voltage Available
SOT-25 Package
Applications
Cellular Telephones
Laptop, Notebook, and Palmtop Computers
Battery-powered Equipment
Hand-held Equipment
Pin Configurations
Part Number
RT9177-
CB
Pin Configurations
5
4
Ordering Information
RT9177-
Package type
B : SOT-25 Type I
BR : SOT-25 Type II
Operating temperature range
C: Commercial standard
Output voltage
24 : 2.4V
25 : 2.5V
:
:
31 : 3.1V
32 : 3.2V
(Plastic SOT-25)
TOP VIEW
1
2
3
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
IN
GND
SHDN
BP
OUT
OUT
GND
IN
SHDN
BP
RT9177-
CBR
5
4
(Plastic SOT-25)
TOP VIEW
1
2
3
Typical Application Circuit
RT9177
V
IN
C
IN
1µF
ON
OFF
IN
GND
SHDN
C
BP
10nF
OUT
C
OUT
1µF
V
OUT
DS9177-00 Feb. 2001
www.richtek-ic.com.tw
1
ETC [ ETC ]
