MIC2536-1YM Datasheet, PDF (1/13 Pages) Micrel Semiconductor – Dual USB Power Distributibution Switch Final Information

MIC2536
Micrel
MIC2536
Dual USB Power Distribution Switch
Final Information
General Description
The MIC2536 is a cost-effective high-side power switch, with
two independently controlled channels, optimized for bus-
powered Universal Serial Bus (USB) applications. Few exter-
nal components are necessary to satisfy USB requirements.
Each switch channel of the MIC2536 will supply up to 100mA
as required for USB bus-powered downstream devices. Fault
current is limited to typically 275mA by fast-acting current-
limit circuitry which minimizes voltage droop on the upstream
port during fault conditions. A flag output with transient filter
indicates fault conditions to the local USB controller but will
ignore short flag signals resulting from inrush current during
hot plug-in events.
Soft start eliminates the momentary voltage droop on other
ports 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 and 3.3V and 5V logic compatible enable
inputs.
The MIC2536 is available in active-high and active-low ver-
sions in 8-lead SOP and MSOP.
Features
• Compliant to USB specifications
• 2.7V to 5.5V operating range
• 150mA minimum continuous load current per channel
• 400mΩ typical on-resistance
• Fast-acting short circuit protection with
thermal shutdown
• Integrated filter eliminates
false overcurrent flag assertions
• Individual open-drain fault flag pins with transient filter
• 3V/5V-compatible enable inputs
• Active-high (-1) and active-low (-2) versions
• Reverse-current blocking in off mode (no “body diode”)
• Soft-start circuit
• 100µA maximum on-state supply current
• <1µA typical off-state supply current
• –40°C to 85°C operation
Applications
• USB keyboard bus-powered hubs
• USB bus-powered docking stations
• Note Book PCs
• PDAs
• General purpose power distribution applications
• PC board hot swap
• Inrush current-limiting
Typical Application
4.50V to 5.25V
Upstream V_BUS
100mA max.
V_BUS
D+
D–
GND
1.5k
MIC5207-3.3
IN
OUT
GND
4.7µF
Data
10k
10k
3.3V USB Controller
VIN
ON/OFF
1µF ^OVERCURRENT
OVERCURRENT
ON/OFF
MIC2536-2
ENA OUTA
FLGA
IN
FLGB GND
ENB OUTB
63µF
0.1µF
63µF
Ferrite
Beads
.01µF
V_BUS
D+
D–
GND
.01µF
V_BUS
D+
D–
GND
Typical Two-Port Bus-Powered Hub
Data
(Two Pair)
to USB
Controller
USB
Port 1
USB
Port 2
UL Recognized Component
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
March 2000
1
MIC2536