MIC2040/2041
Micrel
MIC2040/2041
Single Channel Low Voltage Power Distribution Switch
General Description
The MIC2040 and MIC2041 are high side MOSFET switches
optimized for general purpose power distribution applications
that require circuit protection. The devices switch up to 5.5V
and as low as 0.8V while offering both programmable current
limiting and thermal shutdown to protect the device and the
load. A fault status output is provided in order to detect
overcurrent and thermal shutdown fault conditions. Both
devices employ soft start circuitry to minimize the inrush
current in applications that employ highly capacitive loads.
Additionally, the MIC2040/41 is suited for multi-port USB
applications to satisfy upstream/downstream power require-
ments.
The MIC2041 features a auto-reset circuit breaker mode that
latches the output off upon detecting an overcurrent condition
lasting more than 28ms. The output is reset by removing or
reducing the load.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Features
75mΩ max. on-resistance
0.8V to 5.5V operating range
Adjustable current limit
Up to 1.5A continuous output current
Short circuit protection with thermal shutdown
Circuit breaker mode (MIC2041)
Fault status flag
Undervoltage lockout
Output MOSFET reverse current flow block when
disabled
• Very fast reaction to short-circuits
• Low quiescent current
•
•
•
•
•
•
•
•
•
Applications
•
•
•
•
•
•
•
Docking stations
Notebook PCs
PDAs
Board hot swap
RAID controllers
USB peripherals
ACPI power distribution
Ordering Information
Part Number
Standard
MIC2040-1BMM
MIC2040-2BMM
MIC2041-1BMM
MIC2041-2BMM
Pb-Free
MIC2040-1YMM
MIC2040-2YMM
MIC2041-1YMM
MIC2041-2YMM
Enable
Active-High
Active-Low
Active-High
Active-Low
X
X
Circuit Breaker
Package
10-Pin MSOP
10-Pin MSOP
10-Pin MSOP
10-Pin MSOP
Typical Application
C2
0.1µF
MIC2040-1BM
6
+3.3V
Power
Supply
IN
C3
4.7µF
C1
0.1µF
R1
20kΩ
VBIAS
VIN
EN
/FAULT
ILIM
GND
4
VOUT
8,10
V
OUT
3.3V@ 1A
C
LOAD
33µF
7, 9
1
Logic
Controller
ON/OFF
2
OVERCURRENT
5
UVLOIN
3
(OPEN)
Note:
BothV
IN
pins (7, 8) must be externally tied together.
BothV
OUT
pins (8, 10) must be externally tied together.
I
LIMIT
= 1A.
R
SET
340Ω
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
January 2005
1
M9999-012004
MIC2040/2041
Micrel
Pin Configuration
EN 1
/FAULT 2
UVLOIN 3
GND 4
ILIM 5
10 VOUT
9 VIN
8 VOUT
7 VIN
6 VBIAS
MIC2040/MIC2041
10-Pin MSOP (MM)
Pin Description
Pin Number
1
2
Pin Name
EN
/FAULT
Pin Function
Switch Enable Input: Gate control pin of the output MOSFET available as an
active high (–1) or active low (–2) input signal.
Fault Status Output: Open drain N-Channel device, active low. This pin
indicates an overcurrent, or thermal shutdown condition. For an overcurrent
event, /FAULT is asserted if the duration of the overcurrent condition lasts
longer than 28ms.
Ground Connection: Tie to analog ground.
Current Limit Set: A resistor, R
SET
, connected to this pin sets the current
limit threshold as CLF/R
SET
, where CLF is the current limit factor specified in
the electrical characteristics table. For the MIC2040/41, the continuous
output current range is 0.25A to 1.5A.
Switch Input Supply: The drain of the output MOSFET. The range of input
for the switch is 0.8V to 5.5V. These pins must be externally connected
together.
Switch Output: The source of the output MOSFET. These pins must be
externally connected together.
Bias Supply Input: This input pin supplies bias to operate the switch with
range from 1.6V to 5.5V. When switching voltage (V
IN
) is between 1.6V to
5.5V and the use of a single supply is desired, connect VBIAS to VIN
externally.
Undervoltage Lockout Adjust Input: With this pin left open, the UVLO
threshold is internally set to 1.45V. When the switching voltage (V
IN
) is at or
below 1.6V, connecting an external resistive divider to this input will lower
the UVLO threshold. The total resistance must be less than 200kΩ. See
“Applications Information”
for further detail.
4
5
GND
ILIM
7, 9
VIN
8, 10
6
VOUT
VBIAS
3
UVLOIN
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January 2005
MIC2040/2041
Micrel
Absolute Maximum Ratings
(1)
V
IN
and V
BIAS ..................................................................................
6V
/FAULT, PWRGD Output Voltage ................................... 6V
/FAULT, PWRGD Output Current .............................. 25mA
Junction Temperature Range ................... Internally Limited
ESD Rating
(3)
Human Body Model ................................................... 2kV
Machine Model ........................................................ 200V
Operating Ratings
(2)
Supply Voltage
V
IN
............................................................... 0.8V to 5.5V
V
BIAS
........................................................... 1.6V to 5.5V
Continuous Output Current ........................... 0.25A to 1.5A
Ambient Temperature (T
A
) ........................... –40°C to 85°C
Package Thermal Resistance
(R
θ(J-A)
)
MSOP ................................................................ 160°C/W
Electrical Characteristics
(4)
V
IN
= V
BIAS
= 5V. T
A
= 25°C unless specified otherwise.
Bold
indicates –40°C to +85°C.
Symbol
V
IN
V
BIAS
I
BIAS
Parameter
Switch Input Voltage
Bias Supply Voltage
VBIAS Supply Current - Switch OFF
VBIAS Supply Current - Switch ON
Note 5
Enable Input Voltage
V
IL(max)
V
IH(min)
V
ENHYS
I
EN
R
DS(ON)
I
LEAK
CLF
V
LATCH
I
LATCH
V
OL
I
OFF
V
UV
V
UVHYS
V
UVINTH
V
UVINHYS
Enable Input Threshold Hysteresis
Enable Input Current
Switch Resistance
Output Leakage Current
Current Limit Factor
(6)
Output Reset Threshold
Latched Output Off Current
Output low voltage
(/FAULT)
/FAULT Off Current
Undervoltage Lockout Threshold
Undervoltage Lockout
Threshold Hysteresis
UVLO Adjust Pin Threshold Voltage
UVLO Adjust Pin Threshold Hysteresis
Overtemperature Threshold
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
4. Specification for packaged product only.
5. OFF is V
EN
< 1.0V for MIC2040/MIC2041–1 and V
EN
> 4.0V for MIC2040/MIC2041 –2. ON is V
EN
> 4.0V for MIC2040/MIC2041–1 and
V
EN
< 1.0V for MIC2040/MIC2041 –2.
6. The current limit is determined as follows: I
LIM
= CLF/R
SET
.
Condition
V
IN
≤
V
BIAS
No load
No load
Min
0.8
1.6
Typ
Max
5.5
5.5
Units
V
V
µA
µA
V
V
mV
0.1
250
2.4
3.5
2.5
100
5
400
1.5
V
EN
V
EN
= 0V to 5.5V
V
IN
= V
BIAS
= 3V, 5V
I
OUT
= 500mA
Output off
V
IN
= 3V, 5V; 0.5V
≤
V
OUT
< 0.5V
IN
0.25A
≤
I
OUT
≤
1.5A
V
IN
= 0.8V to 5.5V
V
OUT
rising (MIC2041)
Output latched off (MIC2041)
I
OL
(/FAULT) = 15mA
V
FAULT
= 5V
V
IN
rising
V
IN
falling
–1
.01
50
1
75
10
µA
mΩ
µA
A•Ω
V
280
340
V
IN
–.0.2
400
1
3
5
0.4
1
mA
V
µA
V
V
mV
1.30
1.20
1.45
1.35
100
1.58
1.50
V
IN
rising
V
IN
falling
T
J
increasing
T
J
decreasing
200
180
220
200
20
140
120
240
220
mV
mV
mV
°C
°C
January 2005
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M9999-012004
MIC2040/2041
Micrel
Electrical Characteristics
(7)
Symbol
t
FLAG
t
ON
t
R
t
OFF
t
F
Note:
7. Specification for packaged product only.
Parameter
Flag Response Delay
Output Turn-on Delay,
Output turn-on Rise Time
Output Turn-off Delay
Output Turn-off Fall Time
Condition
V
IN
= V
BIAS
= 3V, 5V
R
LOAD
= 10Ω, C
LOAD
= 1µF
R
LOAD
= 10Ω, C
LOAD
= 1µF
R
LOAD
= 10Ω, C
LOAD
= 1µF
R
LOAD
= 10Ω, C
LOAD
= 1µF
Min
21
400
0.5
Typ
28
600
1
1
24
Max
35
800
1.5
5
Units
ms
µs
ms
µs
µs
Timing Diagrams
50%
V
EN
0
t
ON
10%
(a) MIC2040/41-1
90%
t
OFF
V
OUT
0
50%
V
EN
0
t
ON
t
OFF
90%
V
OUT
0
10%
(b) MIC2040/41-2
Figure 1. Turn-On/Turn-Off Delay
V
EN
0
V
IN
0.2V
Increase the load
V
OUT
0
I
LIMIT
I
OUT
0
t
FLAG
/FAULT
0
Figure 2. Overcurrent Fault Response — MIC2040-2
M9999-012004
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January 2005
MIC2040/2041
Micrel
Test Circuit
V
DD
C2
0.1
m
F
R1
20k
W
V
IN
R3
75k
W
R4
68k
W
R2
20k
W
7, 9
1
2
3
C1
0.1
m
F
6
MIC2040/41-xBM
VBIAS
VOUT
8,10
C
LOAD
VIN
EN
/FAULT
ILIM
UVLOIN
GND
4
5
V
OUT
R
SET
January 2005
5
M9999-012004