DUAL 150mA LDO REGULATOR WITH
PROGRAMMABLE RESET
PRELIMINARY - August 7, 2000
SC1452
TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com
DESCRIPTION
The SC1452 is a state of the art device intended to
provide maximum performance and flexibility in battery
operated systems. It has been designed specifically to
fully support a single Li-Ion battery and its external
charger voltages.
The SC1452 contains two independently enabled, ultra
low dropout voltage regulators (ULDOs). It operates
from an input voltage range of 2.5V to 6.5V, and a wide
variety of output voltage options are available which are
designed to provide an initial tolerance of 鹵1% and
鹵2% over temperature.
Each regulator has an associated active-low reset sig-
nal which is asserted when the voltage output declines
below the preset threshold. Once the output recovers,
the reset continues to be asserted (delayed) for a
predetermined time, 50ms for reset A and 150ms for
reset B. In the case of regulator B, the delay time may
be reduced by the addition of an external capacitor.
The SC1452 has a bypass pin to enable the user to
capacitively decouple the bandgap reference for very
low output noise (down to 50碌Vrms).
The devices utilize CMOS technology to achieve very
low operating currents (typically 150碌A(chǔ) with both out-
puts supplying 150mA). The dropout voltage is typically
165mV at 150mA, helping to prolong battery life. In
addition, the devices are guaranteed to provide 400mA
of peak current for applications which require high initial
inrush current. They have been designed to be used
with low ESR ceramic capacitors to save cost and PCB
area.
The SC1452 comes in the low profile 10-lead MSOP
package.
FEATURES
鈥?
Up to 150mA per regulator output
鈥?
Low quiescent current
鈥?
Low dropout voltage
鈥?
Wide selection of output voltages
鈥?
Stable operation with ceramic caps
鈥?
Tight load and line regulation
鈥?
Current and thermal limiting
鈥?
Reverse input polarity protection
鈥?
<1uA off-mode current
鈥?
Logic controlled electronic enable
鈥?
Programmable reset
鈥?
Full industrial temperature range
APPLICATIONS
鈥?
Cellular telephones
鈥?
Palmtop/Laptop computers
鈥?
Battery-powered equipment
鈥?
Bar code scanners
鈥?
SMPS post regulator/dc to dc modules
鈥?
High efficiency linear power supplies
ORDERING INFORMATION
Part Numbers
SC1452XIMSTR
(1)(2)
Package
MSOP-10
Notes:
(1) Where X denotes voltage options - see table on
page 5.
(2) Only available in tape and reel packaging. A reel
contains 2500 devices.
TYPICAL APPLICATION
U1
3.3V OUT
2.5V OUT
1
2
3
RESET A
RESET B
4
5
OUTA
OUTB
GND
RSTA
RSTB
IN
ENA
BYP
ENB
DLYB
10
9
8
7
6
ENABLE OUTPUT B
3.3V IN
ENABLE OUTPUT A
SC1452JIMS
COUTA
1uF
COUTB
1uF
CBYP
10nF
CDLYB
10nF
CIN
1uF
1
漏 2000 SEMTECH CORP.
652 MITCHELL ROAD NEWBURY PARK CA 91320
SEMTECH
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