POWER MANAGEMENT
Description
The SC5205 is a 150mA ultra low dropout linear
regulator with a built in CMOS/TTL logic level enable
switch. It is designed specifically for battery powered
applications where low quiescent current and low
dropout are critical for battery longevity.
150mA Ultra Low Dropout, Low
Noise Micropower Linear Regulator
PRELIMINARY
Features
Ultra low dropout voltage - 165mV @ 150mA
Guaranteed 150mA output current
Low ground pin current at all loads
<5碌A(chǔ) quiescent current in shutdown
Wide input supply voltage range 2.5V to 16V in
Wide output voltage range
Excellent line regulation
Industrial temperature range
Surface mount packaging (5 pin SOT-23)
SC5205
u
u
u
u
u
u
The SC5205 uses a Semtech proprietary internal PNP
device for the pass element, providing a low dropout
u
voltage of 165mV at a load of 150mA, while maintaining
u
u
a ground pin current of 2750碌A(chǔ).
The output noise is reduced by placing a 10nF capacitor
on pin 4 (bypass).
Applications
Battery Powered Systems
Cellular Telephones
Cordless Telephones
Pagers
Personal Digital Assistants
Portable Instrumentation
Cameras
Portable Consumer Equipment
PCMCIA cards
u
u
Each device contains a bandgap reference, error
u
amplifier, PNP pass element, thermal and current
u
limiting circuitry and resistor divider network for setting
u
output voltage.
u
The SC5205 is packaged in a 5 pin SOT-23 surface mount
u
package for a very small footprint and it requires only a
u
1碌F capacitor on the output and a 0.01碌F on the bypass
u
pin for a minimum amount of external components.
Typical Application Circuit
U1 SC5205
1
VIN
2
3
EN
+
C1
1uF
VIN
GND
EN
BYP
4
C3
1uF
VO
5
VO
+
C2
10nF
Notes:
(1) C
IN
(C1) is needed if the device is far from the supply聮s filter capacitors, or for operation from a battery. A value
of 1.0碌F or greater should be used. C
IN
may be tantalum or aluminum electrolytic.
(2) C
O
(C3) should be a 1碌F or greater tantalum or aluminum electrolytic capacitor. Larger value capacitors will
improve the overall transient response.
(3) C
BYP
(C2 - required) should be placed as close as possible to pin 4 and ground. A 10nF ceramic capacitor is
recommended.
(4) EN may be tied to V
IN
if the shutdown feature is not required. Maximum EN voltage = V
IN
.
Revision 1, January 2001
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www.semtech.com
SEMTECH
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