MIC2042/2043
Micrel
MIC2042/2043
Single Channel, High Current, Low Voltage,
Protected Power Distribution Switch
General Description
Features
TheMIC2042andMIC2043arehigh-sideMOSFETswitches
optimizedforgeneralpurposepowerdistributionapplications
whichrequirecircuitprotection.Thedevicesswitchupto5.5V
and as low as 0.8V while offering both programmable current
limiting and thermal shutdown to protect the device and the
load. A fault status output is provided in order to detect
overcurrent and thermal shutdown fault conditions. Both
devices employ soft-start circuitry to minimize the inrush
current in applications that employ highly capacitive loads.
Additionally, for tighter control over inrush current during
start-up, the output slew-rate may be adjusted by an external
capacitor.
• 60mΩ max. on-resistance
• 0.8V to 5.5V operating range
• Adjustable current limit
• Power-Good detection
• Up to 3A continuous output current
• Short-circuit protection with thermal shutdown
• Adjustable slew-rate control
• Circuit breaker mode (MIC2043)
• Fault status flag
• Undervoltage lockout
• Output MOSFET reverse current flow block when
disabled
• Very fast reaction to short-circuits
• Low quiescent current
The MIC2043 features a auto-reset circuit breaker mode that
latchestheoutputoffupondetectinganovercurrentcondition
lasting more than 28ms. The output is reset by removing or
reducing the load.
Applications
All support documentation can be found on Micrel’s web
site at www.micrel.com.
• Docking stations
• Notebook PCs
• PDAs
• Hot swap board insertions
• RAID controllers
• USB hosts
• ACPI power distribution
Typical Application
+3.3V
C2
0.1µF
MIC2042-1BTS
VOUT
3.3V@ 1.5A
Power
Supply
7
10,11,14
13
VBIAS
VIN
VOUT
C1
R2
OUT1
OUT2
CLOAD
33µF
0.1µF
294kΩ
1%
8, 12
2
PGREF
C3
4.7µF
R1
20kΩ
R3
24.3kΩ
1%
LogicON/OFF
INController
R4
20kΩ
EN
3
9
6
/FAULT
MIC39100-2.5BS
OVERCURRENT
IN
2.5V
1
4
SLEW PWRGD
EN
OUT
GND
ILIM
UVLOIN
GND
(OPEN)
C4*
0.022µF
RSET
200Ω
5
Note:
All VIN pins (8, 12) must be externally tied together.
All VOUT pins (10, 11, 14) must be externally tied together.
ILIMIT ≅ 2A.
Output Power-Good = 3.0V.
*C4 is optional. See "Applications Information."
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
M0512-112603
January 2005
1
MICREL [ MICREL SEMICONDUCTOR ]
