CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved.
C0970500
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
1
Dual USB Overcurrent 1.2A Switches with Independent Controls
Features
Dual switches, each with independent over-current
protection and flag indicator, for 4 USB ports
Two active low Enable controls, one per output
Up to 1.2A continuous current each output
Over-current limits at 1.2A min
10msec min fault blanking delay on OC# outputs
prevents false overcurrent alarms
Prevents backdrive current when host powered off
Low operating current (95A typ.)
Low quiescent current when disabled (<1A max)
Small 8-Lead SOIC package
Applications
PC's, Notebooks, STBs
The CM3512 also prevents backdrive current
flowing into the host from the connected peripheral.
This can occur when V
CC
is removed as the host
powers down, and the peripheral still has normal
power applied. The 5V from the peripheral can
therefore be linked to the host's V
BUS
, potentially
causing backdrive current into the host and
overloading the peripheral power supply.
Pin Diagram
Product Description
California Micro Devices CM3512 is a dual channel
USB overcurrent power switch that provides 5V
power to four independent USB ports. The device
has two power switches that provide the V
BUS
voltage at each USB output port with minimal
voltage drop.
When either of the EN# inputs is at logic low, the
corresponding power switch is ON and V
CC
is
connected to the corresponding output through the
switch. When either of the EN# inputs is at logic
high, the corresponding power switch is OFF, and
no power is available at the output.
Both of the power switches have full over-current
protection. Whenever the current limit out of either
switch is exceeded, the device enters a constant-
current mode, and the output voltage is
progressively reduced to prevent the current from
increasing further. Each switch is independent of the
other, so if a switch is on but is not in overcurrent
mode then it will remain switched on. The OC#
output becomes active low only if the overcurrent
condition exceeds a minimum continuous duration of
10ms. This fault blanking delay prevents false
alarms being reported to the host USB controller.
If the overcurrent condition is severe enough that
the part heats up to the thermal limit T
MAX
, then that
switch will be turned off and the device temperature
cools down. At T
MIN
the switch then turns on again,
and the device heats up again to T
MAX
, and so on,
until the fault is removed.
Typical Application Circuit
Simplified Electrical Schematic
OC1#
V
OUT1
OC2#
V
OUT2
V
CC
EN2#
GND
EN1#
SOIC-8
TOP
V
BUS
V
BUS
V
CC
EN2#
GND
EN1#
OC1#
V
OUT1
OC2#
V
OUT2
V
CC
2 USB Ports
2 USB Ports
EN2#
EN1#
OC1#
V
OUT1
OC2#
V
OUT2
V
CC
Over
current
protect
Over
current
protect
Charge
Pump
Charge
Pump
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
2
Absolute Maximum Ratings
Parameter
Rating
Unit
ESD Protection (All pins, HBM)
2000
V
V
CC
Input Voltage
+ 5.6, Gnd - 0.5
V
Storage Temperature Range
Operating Ambient
Operating Junction
-55 to +150
-40 to +85
-40 to +150*
C
Output Current Loading
Internally limited
A
Package Power Dissipation
0.5
W
*Internally limited
Operating Conditions
(unless specified otherwise)
Parameter
Range
Unit
V
CC
Input Voltage
4.5 to 5.5
V
Ambient Temperature
-40 to +85
C
I
LOAD
per port
B
0 to 1200
00
mA
Electrical Operating Characteristics
(over operating conditions unless specified otherwise)
Symbol Parameter
Conditions
MIN
TYP
MAX UNIT
UVLO V
CC
voltage under which circuit
locks out - will not operate
2.2
2.5
V
R
SW
Switch ON-Resistance
I
LOAD
= 0 to 1200mA; V
CC
= 5V,
T= 25
C
0.13
0.2
V
OUT1
,
V
OUT2
Output Voltage
I
LOAD
= 1000mA, V
CC
= 5.0V,
EN# = 0V, T = 25
C
4.8 V
I
LIM
Over-current
limit
V
CC
= 5V, T = 25
C
1200 mA
t
FBD
Time delay from overcurrent
detection to OC# output
indication (fault blanking delay)
10
20
ms
T
MAX
Temperature at which hot switch
turns off during overcurrent
150 C
T
MIN
Temperature at which cool
switch turns on, after cooling
from T
MAX
125
C
I
R CC
Reverse leakage from outputs
to input
V
CC
= 0V, V
OUT1,2
= 5V,
EN# =high, T=25
C
1
A
I
CC
Operating supply current
EN# = low
95
A
I
CCQ
Quiescent current
EN# = high
1
A
V
IH-EN
EN# input Logic-1 threshold
V
CC
= 5V
2 V
V
IL-EN
EN# input Logic-0 threshold
V
CC
= 5V
0.8
V
I
OHZ-OC
OC# output OFF state leakage
V
CC
= 5V, V
OUT
= 5V
1.0
uA
V
OL-OC
OC# output Logic-0 threshold
I
OC
= 1mA to V
CC
0.4
V
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
3
Pin Functions
V
CC
is the power source.
V
OUT1
provides the power for the first load. The internal
MOSFET switches are designed for very low voltage drops
from the voltage input pins at their full rated currents.
V
OUT2
provides the power for the second load. The internal
MOSFET switches are designed for very low voltage drops
from the voltage input pins at their full rated currents.
Current loads of up to 1200mA are allowed. Current
loads above 1200mA may cause the constant-current
limiting circuit to operate, thereby 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.
During the cold-start interval when the input is initially
applied, internal circuitry provides a soft turn-on for the
switch, which limits peak in-rush current.
EN1#, EN2#
are the active low logic input pins that
are used to control the power switches. Both
switches are independent. Set EN1# and EN2# high
(to >2V) to deselect V
OUT1
and V
OUT2
respectively, and
set EN1# and EN2# low (to <0.8V) to select V
OUT1
and V
OUT2
respectively.
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 delay after the
overcurrent fault condition has been detected, before
these outputs become active. The OC# outputs
become inactive 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.
GND
is the negative reference for all voltages.
Pin Functions
Pin No. Symbol Description
1
GND
Negative reference for all voltages.
2 V
CC
Power supply input.
3
EN1#
Active low Enable pin for V
OUT1
.
4
EN2#
Active low Enable pin for V
OUT2
.
5 OC2#
Active low when
V
OUT2
is in overcurrent mode.
6 V
OUT2
Output voltage #2.
7 V
OUT1
Output voltage #1.
8 OC1#
Active low when
V
OUT1
is in overcurrent mode.
STANDARD PART ORDERING INFORMATION
Pins
Package
Ordering Part Number
1
Part Marking
8 SOIC
CM3512-04SN
CM3512-04SN
Note 1: Parts are shipped in Tape & Reel form unless otherwise specified.
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
4
Response to Momentary Overcurrent Fault
I
OUT
V
OUT
OC#
Die
Temp.
>1200mA
<150'C
V
OUT
drops to reduce I
OUT
OC# goes inactive as
soon as overcurrent
condition stops
<1100mA
OC# goes active
after 10ms (min)
20ms (typ.) delay
I
OUT
V
OUT
OC#
Die
Temp.
T
MAX
= 150'C
T
MIN
= 125'C
150'C
Response to Continuous Overcurrent Fault
V
OUT
drops to reduce I
OUT
Total powerdown when
over-temperature limit
reached
Re-powers when
temperature drops
to 125'C
OC# goes active
after 10ms (min)
20ms (typ.) delay
OC# stays low
Note: The other port stays on (unless it is also in current limit.)
>1200mA
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
5
Typical Operating Characteristics
On-resistance
100
110
120
130
140
150
160
170
180
190
-40
-20
0
20
40
60
80
100
120
140
Temperature ['C]
R
e
s
i
s
t
a
n
c
e
[
m
illio
h
m
s
]
Vcc=5.5V
Vcc=5.0V
Vcc=4.5V
Vcc=4.0V
V
OUT
-I
OUT
characteristic (EN#=0V)
0
1
2
3
4
5
6
0
0.5
1
1.5
2
2.5
3
3.5
I
OUT
[A]
V
OUT
[V]
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
6
OC# Fault Blanking Delay
0
10
20
30
40
50
60
3.5
4
4.5
5
5.5
6
V
CC
[V]
D
e
l
a
y [
m
se
c]
OC# Fault Blanking Period
0
5
10
15
20
25
-40
-20
0
20
40
60
80
100
120
140
Temperature ['C]
T
i
m
e
[m
illis
e
c
o
n
d
s
]
Vcc=5.0V
Vcc=4.0V
Undervoltage Lock-Out (UVLO)
1.95
2
2.05
2.1
2.15
2.2
2.25
-40
-20
0
20
40
60
80
100
120
140
Tem perature ['C]
S
u
p
p
ly
v
o
lt
a
g
e
V
CC
or
V
SB
Y
[V
]
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
7
Supply current vs . s upply voltage
0
20
40
60
80
100
120
4
4.2
4.4
4.6
4.8
5
5.2
5.4
5.6
V
CC
[V]
I
CC
[u
A
]
Supply curre nt [EN#=0V]
0
20
40
60
80
100
120
140
-40
-20
0
20
40
60
80
100
120
Temperature ['C]
Cu
r
r
e
n
t
[
u
A]
Vcc=5.0V
Vcc=4.0V
Supply current [EN#=logic'1']
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
-40
-20
0
20
40
60
80
100
120
Tem perature ['C]
Cu
r
r
e
n
t [u
A]
Vcc=5.0V
Vcc=4.0V
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
8
Turn-on time v s. V
CC
0
20
40
60
80
100
120
140
160
180
4
4.5
5
5.5
V
CC
[V]
T
i
m
e
[
u
se
c]
Cout=0.1u
Cout=1u
Turn-off time vs. V
CC
0
5
10
15
20
25
30
4
4.5
5
5.5
V
CC
[V]
T
i
m
e
[
u
se
c]
Cout=0.1u
Cout=1u
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
9
Turn-on time
0
50
100
150
200
250
-40
-20
0
20
40
60
80
Temperature ['C]
T
i
m
e
[
u
sec]
Vcc=5.5V
Vcc=4.5V
Turn-off time
0.0
1.0
2.0
3.0
4.0
5.0
-40
-20
0
20
40
60
80
Temperature ['C]
T
i
m
e
[
u
sec]
Vcc=5.5V
Vcc=4.5V
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
10
Normalized Overcurrent indicator trip point
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
1.40
1.50
-40
-20
0
20
40
60
80
100
120
Temperature ['C]
C
u
r
r
e
nt
[
n
o
r
m
a
liz
e
d
]
Vcc=5.5V
Vcc=4.5V
CALIFORNIA MICRO DEVICES
Preliminary
CM3512
2003 California Micro Devices Corp. All rights reserved
11/10/03
430 N. McCarthy Blvd, Milpitas, California 95035 Tel: (408) 263-3214 Fax: (408) 263-7846 www.calmicro.com
11
SOIC-8 Package Dimensions
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