POWER MANAGEMENT
Description
The SC1456 contains two low dropout linear regulators
that operate from a +2.5V to +6V input range and
deliver up to 150mA. PMOS pass transistors allow a low
110µA supply current per device to remain independent
of load, making these devices ideal for battery operated
portable equipment such as cellular phones, cordless
phones and personal digital assistants.
Each device can be powered from a separate supply
voltage or the same supply voltage for maximum
flexibility. The output voltage of each device can be
preset or adjusted with an external resistor divider. Other
features include independant low powered shutdown,
short circuit protection, thermal shutdown protection and
reverse battery protection for each regulator. The
SC1456 comes in the tiny 10 lead MSOP package (lead
free, fully WEEE and RoHS compliant available).
Typical Application Circuits
SC1456
Dual 150mA Ultra Low
Dropout, Low Noise Regulator
Features
Two guaranteed 150 mA outputs
Designed to operate with ceramic capacitors
Fixed or adjustable outputs
Very small external components
Low 75µV output noise
RMS
Very low supply currents
Thermal overload protection
Reverse battery protection
Individual low power shutdown
Full industrial temperature range
Surface mount packaging (10 pin MSOP)
Applications
Battery Powered Systems
Cellular Telephones
Cordless Telephones
Personal Digital Assistants
Portable Instrumentation
Modems
PCMCIA cards
VIN1
VIN2
(OR VIN1)
C1
C2
1uF
1uF
U1
10 IN1
1 EN1
5 IN2
6 EN2
SC1456
OUT1 9
OUT2 4
SET1 3
SET2 8
GND GND
2
7
VOUT1 = PRESET
VOUT2 = PRESET
C3
C4
1uF
1uF
VIN1
VIN2
(OR VIN1)
C1
C2
1uF
1uF
Output Voltages Set Internally
U1
10 IN1
SC1456
OUT1 9
1 EN1
OUT2 4
5 IN2
SET1 3
R1
6 EN2
SET2 8
GND GND
2
7
R2
VOUT1 (SEE EQUATION)
VOUT2 = PRESET
C3
2.2uF
C4
1uF
VOUT1
=
1.250
•
1 +
R1
R2
R2 ≤ 120kΩ
Revision: November 16, 2005
Output 1 Set Externally and Output 2 Set Internally
1
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