CALIFORNIA MICRO DEVICES
Pin Functions
SEL pin is above 2V it will be selected, and V
SBY
will be
deselected.
PRELIMINARY
CM3511
During the cold-start interval when the input is initially
applied, internal circuitry provides a soft turn-on for
the switches, which limits peak in-rush current.
V
CC
is the higher current power source. Whenever the
SEL pin is below 0.8V it will be selected, and V
CC
will
be deselected. The two V
SBY
power switches can only
supply 200mA each.
Note that the internal supply current (95uA typ.) will be
taken from whichever input supply pin (V
CC
or V
SBY
) is
higher.
V
SB
V
SBY
is the lower current power source. Whenever the
SEL
is the 3-level logic input pin that is used to
control which of the power switch pairs are turned on.
Set SEL high to select V
CC
, set SEL low to select
V
SBY
, or allow SEL to float to deselect both power
switches. The external device driving the SEL pin
must able to source and sink 100µA while
maintaining the proper V
IL
/V
IH
levels.
V
OUT1
provides the power for a USB port. The internal
OC1#, OC2#
are independent, active low open-
drain outputs, indicating an overcurrent fault condition
has been detected at V
OUT1
or V
OUT2
. There is a built-
in 10msec (min.) fault blanking period after the
overcurrent fault condition has been detected, before
these outputs become active. The OC# outputs
become deasserted only when both the overcurrent
condition stops and when the voltage drop across the
switch is less than 1V. External pull-up resistors of
10k - 100k are required if the OC# outputs are used.
Because they are open-drain, the two OC# outputs
can be shorted together to make one OC# signal.
MOSFET switches are designed for low voltage drops
from the voltage input pins at their full rated currents.
internal MOSFET switches are designed for low voltage
drops from the voltage input pins at their full rated
currents.
V
OUT2
provides the power for a second USB port. The
Current loads of up to 1.2A are allowed (sourced from
Vcc).
Current loads above 1.2A may cause the constant-
current limiting circuit to operate – reducing the output
voltage.
Continuous over-current loads will cause the part’s
internal temperature to rise. If the internal temperature
exceeds 150’C then any switch that is in overcurrent
mode will be immediately turned off. Any switch that is
not in overcurrent mode will remain on – it will not be
affected by the over-temperature detection. Once the
part has cooled to 125’C then the switch or switches
that were in overcurrent mode will be automatically
turned on again.
Pin Functions
Pin No.
1
2
3
4
5
6
7
8
Symbol
GND
V
CC
V
SBY
SEL
OC2#
V
OUT2
V
OUT1
OC1#
GND
is the negative reference for all voltages.
Description
Negative reference for all voltages.
High current positive supply input.
Standby positive supply input. Also provides internal power.
3-level logic input. High = V
CC
, Low = V
SBY
, Floating = both off
Active low when
V
OUT2
is in overcurrent mode.
Output voltage internally switched to either V
CC
or V
SBY
input source.
Output voltage internally switched to either V
CC
or V
SBY
input source.
Active low when
V
OUT1
is in overcurrent mode.
STANDARD PART ORDERING INFORMATION
Pins
8
11/10/03
Package
SOIC
Ordering Part Number
CM3511-04SN
1
Part Marking
CM3511-04SN
© 2003 California Micro Devices Corp. All rights reserved
430 N. McCarthy Blvd, Milpitas, California 95035
Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
3
CALMIRCO [ CALIFORNIA MICRO DEVICES CORP ]
