LM3880_14 Datasheet, PDF (1/20 Pages) Texas Instruments – Power Sequencer

LM3880, LM3880Q
www.ti.com
SNVS451H – AUGUST 2006 – REVISED JULY 2011
LM3880/LM3880Q Power Sequencer
Check for Samples: LM3880, LM3880Q
FEATURES
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•2 Easiest method to sequence rails
• Power up and power down control
• Input voltage range of 2.7V to 5.5V
• Small footprint SOT23-6
• Low quiescent current of 25 µA
• Standard timing options available
• Customization of timing and sequence
available through factory programmability
• LM3880Q is AEC-Q100 Grade 1 qualified and is
manufactured on an Automotive Grade Flow
APPLICATIONS
• Multiple supply sequencing
• Microprocessor / Microcontroller sequencing
• FPGA sequencing
• Automotive
DESCRIPTION
The LM3880 Power Sequencer offers the easiest method to control power up and power down of multiple power
supplies (switchers or linear regulators). By staggering the startup sequence, it is possible to avoid latch
conditions or large in-rush currents that can affect the reliability of the system.
Available in a SOT23-6 package, the Power Sequencer contains a precision enable pin and three open drain
output flags. Upon enabling the LM3880 the three output flags will sequentially release, after individual time
delays, permitting the connected power supplies to startup. The output flags will follow a reverse sequence
during power down to avoid latch conditions.
EPROM capability allows every delay and sequence to be fully adjustable. Contact National Semiconductor if a
non-standard configuration is required.
Typical Application Circuit
Input
Supply
Enable
VCC
FLAG 1
EN
FLAG 2
FLAG 3
GND
Power Supply 1
Enable
Power Supply 2
Enable
Power Supply 3
Enable
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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