MIC2524/2527
Micrel
MIC2524/2527
Quad USB Power Control Switch
Not Recommended for New Designs
Refer to MIC2027
General Description
The MIC2524 and MIC2527 are cost-effective high-side
power switches with four independently controlled channels,
optimized for self-powered and bus-powered Universal Se-
rial Bus (USB) applications. Few external components are
necessary to satisfy USB requirements.
The MIC2524/7 satisfies the following USB requirements:
each switch channel supplies up to 500mA as required by
USB downstream devices; the switch’s low on-resistance
meets USB voltage drop requirements; fault current is limited
to typically 750mA, well below the UL 25VA safety require-
ments; and a flag output is available to indicate fault condi-
tions to the local USB controller. Soft start eliminates the
momentary voltage drop on the upstream port that may occur
when the switch is enabled in bus-powered applications.
Additional features include thermal shutdown to prevent
catastrophic switch failure from high-current loads,
undervoltage lockout (UVLO) to ensure that the device re-
mains off unless there is a valid input voltage present, and
3.3V and 5V logic compatible enable inputs.
The MIC2524/7 is available in active-high and active-low
versions in 16-pin DIP and SOIC packages.
Features
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Compliant to USB specifications
UL Recognized Component
4 independent switches
3V to 5.5V input
500mA minimum continuous load current per port
140mΩ maximum on-resistance (MIC2524)
1.25A maximum short circuit current limit
Individual open-drain fault flag pins
220µA on-state supply current
1µA typical off-state supply current
Output can be forced higher than input (off-state)
Thermal shutdown
2.4V typical undervoltage lockout (UVLO)
1ms turn-on (soft-start) and fast turnoff
Active-high or active-low enable versions
16-pin SOIC and DIP packages
USB bus-powered hubs
USB self-powered hubs
USB monitors
USB printers
Applications
Typical Application
MIC2527
5.1V
±
3%
5V
±
1%
or
MIC2524
5V
±3%
MIC5207-3.3
LDO Regulator
IN
4.7
µF
OUT
1µF
GND
Ferrite
Bead
10k
27k
3.3V USB Controller
V+
ON/OFF
OVERCURRENT
MIC2524
MIC2527
ENA
FLGA
ENB
FLGB
D+
D–
GND
ENC
FLGC
END
FLGD
Bold
lines indicate
0.1" wide, 1-oz. copper
high-current traces.
* 33µF, 16V tantalum or 100µF, 10V electrolytic per port
IN
IN
OUTA
OUTB
OUTC
OUTD
GND
GND
33µF*
0.01µF
0.1
µF
33µF*
0.01µF
33µF*
0.01µF
V
BUS
D+
D–
GND
Downstream
USB
Port 1
500mA max.
V
BUS
D+
D–
GND
Downstream
USB
Port 2
500mA max.
V
BUS
D+
D–
GND
Downstream
USB
Port 3
500mA max.
V
BUS
33µF*
0.01µF
D+
D–
GND
Downstream
USB
Port 4
500mA max.
4-Port Self-Powered Hub
UL Recognized Component
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
June 1999
1
MIC2524/2527
MICREL [ MICREL SEMICONDUCTOR ]
