MIC2027 Datasheet, PDF (1/16 Pages) Micrel Semiconductor – Quad USB Power Distribution Switch Preliminary Information

MIC2027/2077
Micrel
MIC2027/2077
Quad USB Power Distribution Switch
Preliminary Information
General Description
The MIC2027 and MIC2077 are quad high-side MOSFET
switches optimized for general-purpose power distribution
requiring circuit protection. The MIC2027/77 are internally
current limited and have thermal shutdown that protects the
device and load.
The MIC2077 offers “smart” thermal shutdown that reduces
current consumption in fault modes. When a thermal shut-
down fault occurs, the output is latched off until the faulty load
is removed. Removing the load or toggling the enable input
will reset the device output.
Both devices employ soft-start circuitry that minimizes inrush
current in applications where highly capacitive loads are
employed.
A fault status output flag is asserted during overcurrent and
thermal shutdown conditions. Transient current limit faults
are internally filtered.
The MIC2027/77 is available in narrow (150 mil) and wide
(300 mil) SOP (small outline packages).
Features
• 140mΩ maximum on-resistance per channel
• 2.7V to 5.5V operating range
• 500mA minimum continuous current per channel
• Short-circuit protection with thermal shutdown
• Thermally isolated channels
• Fault status flag with 3ms filter
eliminates false assertions
• Undervoltage lockout
• Reverse current flow blocking (no “body diode”)
• Circuit breaker mode (MIC2077)
reduces power consumption
• Logic-compatible inputs
• Soft-start circuit
• Low quiescent current
Pin-compatible with MIC2524 and MIC2527
Applications
• USB peripherals
• General purpose power switching
• ACPI power distribution
• Notebook PCs
• PDAs
• PC card hot swap
Typical Application
5V ± 3%
MIC5203-3.3
LDO Regulator
IN
OUT
4.7
µF
GND
10k
3.3V USB Controller
V+
ON/OFF
1µF OVERCURRENT
D+
D– _GND
Bold lines indicate
0.1" wide, 1-oz. copper
high-current traces.
* 33µF, 16V tantalum or 100µF, 10V electrolytic per port
MIC2027
ENA
IN
FLGA
IN
ENB OUTA
FLGB OUTB
ENC OUTC
FLGC OUTD
END
FLGD
GND
GND
33µF*
0.1
µF
33µF*
33µF*
33µF*
Ferrite
Bead
0.01µF
V_BUS
D+
D–
GND
0.01µF
V_BUS
D+
D–
GND
0.01µF
V_BUS
D+
D–
GND
0.01µF
V_BUS
D+
D–
GND
Downstream
USB
Port 1
500mA max.
Downstream
USB
Port 2
500mA max.
Downstream
USB
Port 3
500mA max.
Downstream
USB
Port 4
500mA max.
4-Port Self-Powered Hub
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
June 2000
1
MIC2027/2077