ST2044 Datasheet, PDF (1/13 Pages) STMicroelectronics – Current limited Power distribution switches

ST2044
Current limited
Power distribution switches
Features
■ 80mΩ high-side MOSFET switch
■ 500mA continuos current per channel
■ independent thermal and short-circuit
protection with overcurrent logic output
■ Operating range from 2.7V to 5.5V
■ CMOS- and TTL-compatible enable inputs
■ 10ms OC_N fault blanking
■ 2.5ms typical rise time
■ Under voltage lock out
■ 20µA maximum standby supply current
■ Ambient temperature range, -40°C to 85°C
■ ESD protection
Description
The ST2044 power distribution switches is
intended for application where heavy capacitive
loads and short circuits are likely to be
encountered. These devices incorporate 80mΩ
N-channel MOSFET high-side power switches for
power-distribution systems that require multiple
powers switches in a single package. Each switch
is controlled by an independent logic enable input.
Gate drive is provided by an internal charge pump
designed to control the power-switch rise times
and fall times to minimize current surges during
switching. The charge pump requires no external
components and allows operation from supplies
as low as 2.7 V.
SO-16
When the output load exceeds the current-limit
threshold or a short is present, these devices limit
the output current to a safe level by switching into
a constant-current mode, pulling the overcurrent
(OCx) logic output low. A 10ms deglitching circuit
provides fault-blanking feature, preventing the
OC_N pin to be asserted during hot-insertion or
short spikes of overcurrent conditions.
When continuous heavy overloads and short
circuits increase the power dissipation in the
switch, causing the junction temperature to rise, a
thermal protection circuit shuts off the switch to
prevent damage. Recovery from a thermal
shutdown is automatic once the device has
cooled sufficiently. Internal circuitry ensures the
switch remains off until valid input voltage is
present. These power-distribution switches are
designed to current limit at 0.9 A.
Table 1. Device summary
Part number
ST2044BD
ST2044BDR
Package
SO-16
SO-16
Packaging
Tube
(50 parts per tube, 40 tube per box)
Tape and reel (2500 parts per reel)
May 2007
Rev 5
1/13
www.st.com
13