MIC2009YM6 TX Micrel Inc, MIC2009YM6 TX Datasheet - Page 12

• Manufacturer Part Number: MIC2009YM6 TX
• Manufacturer: Micrel Inc

Specifications of MIC2009YM6 TX

• Short Circuit Current Limit: 0.2 to 2A
• Input Voltage Range: 2.5 to 5.5V
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 6
• Package Type: SOT-23
• Lead Free Status / RoHS Status: Compliant

September 2005
Micrel
Enable
ENABLE is a HIGH true control signal, which activates
the main MOSFET switch. ENABLE will operate with
logic running from supply voltages as low as 1.8V.
ENABLE can be wire-OR’d with other MIC2009/2019s
or similar devices without damage to the device.
ENABLE may be driven higher than V
than 5.5V.
FAULT/
FAULT/ is an N-channel ‘open drain’ output, which is
asserted (LOW true) when MIC2009/2019’s either
begins current limiting or enters thermal shutdown.
In MIC2009, FAULT/ asserts after a brief delay period,
usually 32 ms. This delay ensures that FAULT/ is
asserted only upon
conditions and that transitory event error reports are
filtered out.
MIC2019’s FAULT/ asserts at the end of the Kickstart
period. This masks initial current surges, such as would
be seen by a motor load starting up. If the load current
remains above the current limit threshold, after the
Kickstart has timed out, then FAULT/ will be asserted.
After a fault clears, FAULT/ remains asserted for the
delay period; 32ms for the MIC2009 or 128 ms for the
MIC2019.
Because FAULT/ is an ‘open drain’ it must be pulled
HIGH with an external resistor output and it may be
wire-OR’d with other similar outputs, sharing a single
pull-up resistor. FAULT/ may be tied to a pull-up voltage
source which is higher than V
5.5V.
valid, enduring,
IN
, but no greater than
IN
, but no higher
over-current
12
Slew Rate Control
Large capacitive loads can create significant current
surges when charged through a high-side switch such
as the MIC2009/2019. For this reason, MIC2009/2019
provides built-in slew rate control to limit the initial inrush
currents upon enabling the power MOSFET switch.
Slew rate control is active upon powering up, and upon
re-enabling the load. At shutdown, the discharge slew
rate is controlled by the external load and output
capacitor.
Thermal Shutdown
Thermal
MIC2009/2019 from damage should the die temperature
exceed safe operating levels. Thermal shutdown shuts
off the output MOSFET and asserts the FAULT/ output if
the die temperature reaches 145°C.
The MIC2009/2019 will automatically resume operation
when the die temperature cools down to 135°C. If
resumed operation results in reheating of the die, then
another
MIC2009/2019 will continue cycling between ON and
OFF states until the offending load has been removed.
Depending upon PCB layout, package type, ambient
temperature, etc., hundreds of milliseconds may elapse
from the incidence of a fault to the output MOSFET
being shut off. This delay is due to thermal time
constants within the system itself. In no event will the
device be damaged due to thermal overload because
die temperature is monitored continuously by on-chip
circuitry.
shutdown
shutdown
is
cycle
employed
will
MIC2009/MIC2019
occur
to
[phone]
M9999-092305
protect
and
the
the