MIC2527 Datasheet, PDF (1/12 Pages) Micrel Semiconductor – Quad USB Power Control Switch

MIC2527
Micrel
MIC2527
Quad USB Power Control Switch
Advance Information
General Description
The MIC2527 is a cost-effective high-side power switch with
four independently controlled channels, optimized for self-
powered and bus-powered Universal Serial Bus (USB) appli-
cations. Few external components are necessary to satisfy
USB requirements.
The MIC2527 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 MIC2527 is available in active-high and active-low ver-
sions in 16-pin DIP and SOIC packages.
Features
• Compliant to USB specifications
• 4 independent switches
• 3V to 5.5V input
• 500mA minimum continuous load current per port
• 300mΩ maximum on-resistance
• 750mA typical 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
Applications
• USB bus-powered hubs
• USB self-powered hubs
• USB monitors
• USB printers
Typical Application
5.1V ± 3%
or
5V ±1%
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
100k
MIC2527
ENA
FLGA
ENB
IN
IN
OUTA
FLGB
ENC
FLGC
END
FLGD
OUTB
OUTC
OUTD
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
May 7, 1998
1
MIC2527