Micrel MIC2008YML Fixed and adjustable current limiting power distribution switch Datasheet

MIC20XX Family
Fixed and Adjustable Current Limiting
Power Distribution Switches
General Description
Features
MIC20XX family of switches are current limiting, high-side
power switches, designed for general purpose power
distribution and control in digital televisions (DTV),
printers, set top boxes (STB), PCs, PDAs, and other
peripheral devices. See Functionality Table on page 6
and Pin Configuration Drawings on page 7.
MIC20XX family’s primary functions are current limiting
and power switching. They are thermally protected and
will shutdown should their internal temperature reach
unsafe levels, protecting both the device and the load,
under high current or fault conditions
Features include fault reporting, fault blanking to eliminate
noise-induced false alarms, output slew rate limiting,
under voltage detection, automatic-on output, and enable
pin with choice of either active low or active high enable.
The FET is self-contained, with a fixed or user adjustable
current limit. The MIC20XX family is ideal for any system
where current limiting and power control are desired.
The MIC201X (3 ≤ x ≤ 9) subfamily offers a unique new
patented feature: KICKSTART™, which allows
momentary high current surges up to the secondary
current limit (ILIMIT_2nd) without sacrificing overall system
safety.
The MIC20XX family is offered, depending on the desired
features, in a space saving 5-pin SOT-23, 6-pin SOT-23,
®
and 2mm x 2mm MLF packages.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
•
•
•
•
•
•
•
•
•
•
•
•
•
70mΩ typical on-resistance @ 5V
170mΩ typical on-resistance @ 5V (MIC2005A)
Enable active high or active low *
2.5V – 5.5V operating range
Pre-set current limit values of 0.5A, 0.8A, and 1.2A *
User adjustable current limit from 0.2A to 2.1A *
Under voltage lock-out (UVLO)
Variable UVLO allows adjustable UVLO thresholds *
Automatic load discharge for capacitive loads *
Soft start prevents large current inrush
Adjustable slew rate allows custom slew rates *
Automatic-on output after fault
Thermal Protection
* Available on some family members
Applications
•
•
•
•
•
•
•
•
Digital televisions (DTV)
Set top boxes
PDAs
Printers
USB / IEEE 1394 power distribution
Desktop and laptop PCs
Game consoles
Docking stations
_________________________________________________________________________________________________________
Typical Application
5V Supply
MIC20X5
Logic
Controller
VIN
VOUT
(2,3)
GND
VIN
ON/OFF
OVERCURRENT/
1µF
EN
IADJ
VBUS
120µF
USB
Port
(1,3)
FAULT/
Figure 1. Typical Application Circuit
Notes:
(1) Depending on the family member this pin can function as FAULT/, IADJ, or VUVLO.
(2) Depending on the family member this pin can function as IADJ, or CSLEW.
(3) See Pin Configuration and Functional Diagram.
KICKSTART is a trademark of Micrel, Inc.
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
CableCARD is a trademark of CableLabs.
Protected by U.S. Patent No. 7,170,732
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
January 2009
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Ordering Information
MIC2003/2013
(1)
Part Number
(2)
Marking
Current Limit
MIC2003-0.5YM5
FD05
0.5A
MIC2003-0.8YM5
FD08
0.8A
MIC2003-1.2YM5
FD12
1.2A
MIC2003-0.5YML
D05
0.5A
MIC2003-0.8YML
D08
0.8A
MIC2003-1.2YML
D12
1.2A
MIC2013-0.5YM5
FL05
0.5A
MIC2013-0.8YM5
FL08
0.8A
MIC2013-1.2YM5
FL12
1.2A
MIC2013-0.5YML
L05
0.5A
MIC2013-0.8YML
L09
0.8A
MIC2013-1.2YML
L12
1.2A
Kickstart
Package
5-Pin SOT-23
No
®
6-Pin 2mm x 2mm MLF
5-Pin SOT-23
Yes
®
6-Pin 2mm x 2mm MLF
MIC2004/2014
(1)
Part Number
Notes:
(2)
Marking
Current Limit
MIC2004-0.5YM5
FE05
0.5A
MIC2004-0.8YM5
FE08
0.8A
MIC2004-1.2YM5
FE12
1.2A
MIC2004-0.5YML
E05
0.5A
MIC2004-0.8YML
E08
0.8A
MIC2004-1.2YML
E12
1.2A
MIC2014-0.5YM5
FM05
0.5A
MIC2014-0.8YM5
FM08
0.8A
MIC2014-1.2YM5
FM12
1.2A
MIC2014-0.5YML
M05
0.5A
MIC2014-0.8YML
M09
0.8A
MIC2014-1.2YML
M12
1.2A
Kickstart
Package
5-Pin SOT-23
No
®
6-Pin 2mm x 2mm MLF
5-Pin SOT-23
Yes
®
6-Pin 2mm x 2mm MLF
1. All MIC20XX Family parts are RoHS compliant lead free.
2. Over/Under-bar symbol ( ¯ / _ ) may not be to scale. On the package the over/under symbol begins above/below the first character of
the marking.
January 2009
2
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Ordering Information (continued)
MIC2005
(1)
Part Number
(2)
Marking
Current Limit
Enable
MIC2005-0.5YM6
FF05
0.5A
Active High
MIC2005-0.8YM6
FF08
0.8A
Active High
MIC2005-1.2YM6
FF12
1.2A
Active High
MIC2005-0.5YML
F05
0.5A
Active High
MIC2005-0.8YML
F08
0.8A
Active High
MIC2005-1.2YML
F12
1.2A
Active High
Current Limit
Enable
Kickstart
Package
6-Pin SOT-23
No
®
6-Pin 2mm x 2mm MLF
MIC2005L
(1)
Part Number
(2)
Marking
MIC2005-0.5LYM5
5LFF
0.5A
Active Low
MIC2005-0.8LYM5
8LFF
0.8A
Active Low
MIC2005-1.2LYM5
4LFF
1.2A
Active Low
Current Limit
Enable
Kickstart
Package
No
5-Pin SOT-23
Kickstart
Package
MIC2005A
(1)
Part Number
(2)
Marking
MIC2005A-1YM5
FA51
0.5A
Active High
MIC2005A-2YM5
FA52
0.5A
Active Low
MIC2005A-1YM6
FA53
0.5A
Active High
MIC2005A-2YM6
FA54
0.5A
Active Low
Current Limit
Enable
5-Pin SOT-23
No
6-Pin SOT-23
MIC2015
(1)
Part Number
(2)
Marking
MIC2015-0.5YM6
FN05
0.5A
Active High
MIC2015-0.8YM6
FN08
0.8A
Active High
MIC2015-1.2YM6
FN12
1.2A
Active High
MIC2015-0.5YML
N05
0.5A
Active High
MIC2015-0.8YML
N08
0.8A
Active High
MIC2015-1.2YML
N12
1.2A
Active High
Notes:
Kickstart
Package
6-Pin SOT-23
Yes
®
6-Pin 2mm x 2mm MLF
1. All MIC20XX Family parts are RoHS compliant lead free.
2. Over/Under-bar symbol ( ¯ / _ ) may not be to scale. On the package the over/under symbol begins above/below the first character of
the marking.
January 2009
3
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Ordering Information (continued)
MIC2006/2016
(1)
Part Number
Notes:
(2)
Marking
Current Limit
MIC2006-0.5YM6
FG05
0.5A
MIC2006-0.8YM6
FG08
0.8A
MIC2006-1.2YM6
FG12
1.2A
MIC2006-0.5YML
G05
0.5A
MIC2006-0.8YML
G08
0.8A
MIC2006-1.2YML
G12
1.2A
MIC2016-0.5YM6
FP05
0.5A
MIC2016-0.8YM6
FP08
0.8A
MIC2016-1.2YM6
FP12
1.2A
MIC2016-0.5YML
P05
0.5A
MIC2016-0.8YML
P09
0.8A
MIC2016-1.2YML
P12
1.2A
Kickstart
Package
6-Pin SOT-23
No
®
6-Pin 2mm x 2mm MLF
6-Pin SOT-23
Yes
®
6-Pin 2mm x 2mm MLF
1. All MIC20XX Family parts are RoHS compliant lead free.
2. Over/Under-bar symbol ( ¯ / _ ) may not be to scale. On the package the over/under symbol begins above/below the first character of
the marking.
January 2009
4
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Ordering Information (continued)
MIC2007/2017
(1)
Part Number
(2)
Marking
MIC2007YM6
FHAA
MIC2007YML
HAA
MIC2017YM6
FQAA
MIC2017YML
QAA
Current Limit
Kickstart
No
0.2A – 2.0A
Yes
Package
6-Pin SOT-23
®
6-Pin 2mm x 2mm MLF
6-Pin SOT-23
®
6-Pin 2mm x 2mm MLF
MIC2008/2018
(1)
Part Number
(2)
Marking
MIC2008YM6
FJAA
MIC2008YML
JAA
MIC2018YM6
FRAA
MIC2018YML
RAA
Current Limit
Kickstart
No
0.2A – 2.0A
Yes
Package
6-Pin SOT-23
®
6-Pin 2mm x 2mm MLF
6-Pin SOT-23
®
6-Pin 2mm x 2mm MLF
MIC2009/2019
(1)
Part Number
Notes:
(2)
Marking
MIC2009YM6
FKAA
MIC2009YML
KAA
MIC2019YM6
FSAA
MIC2019YML
SAA
Current Limit
Kickstart
No
0.2A – 2.0A
Yes
Package
6-Pin SOT-23
®
6-Pin 2mm x 2mm MLF
6-Pin SOT-23
®
6-Pin 2mm x 2mm MLF
1. All MIC20XX Family parts are RoHS compliant lead free.
2. Over/Under-bar symbol ( ¯ / _ ) may not be to scale. On the package the over/under symbol begins above/below the first character of
the marking.
January 2009
5
M9999-012109-A
Micrel, Inc.
MIC20XX Family
MIC20XX Family Member Functionality
Part Number
Normal
Limiting
Pin Function
Kickstart
(1)
I Limit
ILIMIT
ENABLE
High
ENABLE
Low
CSLEW
FAULT/
─
─
─
─
─
─
─
─
▲
─
─
─
─
▲
─
▲
─
▲
▲
─
─
─
─
▲
(6)
▲
─
─
(6)
▲
─
─
(6)
▲
─
─
(5)
VUVLO
Load
Discharge
2003
2013
2004
2014
2005
2015
2005L
─
(2)
2005A-1
─
(2)
─
▲
─
▲
2005A-2
─
(2)
─
─
▲
▲
─
▲
─
▲
─
▲
─
▲
▲
─
▲
─
─
▲
▲
▲
─
▲
─
─
─
▲
▲
─
─
▲
─
─
2006
2016
2007
2017
2008
2018
2009
2019
Notes:
1.
2.
3.
4.
5.
6.
Fixed
Adj.
(3)
(4)
─
Kickstart provides an alternate start-up behavior; however, pin-outs are identical.
Kickstart not available.
Fixed = Factory programmed current limit.
Adj. = User adjustable current limit.
VUVLO = Variable UVLO (Previously called DML).
CSLEW not available in 5-pin package.
MIC20XX Family Member Pin Configuration Table
Part Number
Pin Number
Normal
Limiting
Kickstart
2003
1
2
3
4
5
6
2013
VIN
GND
─
─
─
VOUT
2004
2014
VIN
GND
EN
─
─
VOUT
2005
2015
VIN
GND
EN
FAULT/
CSLEW
2005L
2005A
─
(1)
─
(1)
2006
2016
2007
2017
2008
2018
2009
2019
Notes:
1.
2.
3.
4.
5.
I Limit
Fixed
(2)
VIN
VIN
Adj.
(3)
GND
EN
GND
EN
FAULT/
FAULT/
(4)
VOUT
CSLEW
(5)
VOUT
CSLEW
(5)
VOUT
VIN
GND
EN
VUVLO
CSLEW
VOUT
VIN
GND
EN
IADJ
CSLEW
VOUT
VIN
GND
EN
IADJ
CSLEW
VOUT
VIN
GND
EN
FAULT/
IADJ
VOUT
Kickstart not available.
Fixed = Factory programmed current limit.
Adj. = User adjustable current limit.
VUVLO = Variable UVLO (Previously called DLM).
CSLEW not available in 5-pin package.
January 2009
6
M9999-012109-A
Micrel, Inc.
MIC20XX Family
MIC20XX Family Member Pin Configuration Drawings
Fixed Current Limit
VIN 1
5 VOUT
GND 2
NC 3
4 NC
VOUT
1
6
VIN
NC
2
5
GND
NC
3
4
NC
(Top View)
MIC20X3
VIN 1
5 VOUT
GND 2
ENABLE 3
4 NC
VOUT
1
6
VIN
NC
2
5
GND
NC
3
4
ENABLE
(Top View)
MIC20X4
VIN 1
VIN 1
5 VOUT
GND 2
ENABLE 3
4 FAULT/
6 VOUT
GND 2
5 CSLEW
ENABLE 3
4 FAULT/
VOUT
1
6
VIN
CSLEW
2
5
GND
FAULT/
3
4
ENABLE
(Top View)
MIC2005-X.XL / MIC2005A
VIN 1
MIC20X5
6 VOUT
GND 2
5 CSLEW
ENABLE 3
4 VUVLO
MIC20X5
VOUT
1
6
VIN
CSLEW
2
5
GND
VUVLO
3
4
ENABLE
(Top View)
MIC20X6
January 2009
7
M9999-012109-A
Micrel, Inc.
MIC20XX Family
MIC20XX Family Member Pin Configuration Drawings (continued)
Adjustable Current Limit
VIN 1
GND 2
ENABLE 3
6 VOUT
5 CSLEW
4 ILIMIT
VOUT
1
6
VIN
CSLEW
2
5
GND
ILIMIT
3
4
ENABLE
(Top View)
MIC20X7 / 20X8
VIN 1
6 VOUT
VOUT
1
6
VIN
GND 2
5 ILIMIT
ILIMIT
2
5
GND
FAULT/
3
4
ENABLE
ENABLE 3
4 FAULT/
(Top View)
MIC20X9
January 2009
8
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Descriptions
These pin and signal descriptions aid in the differentiation of a pin from electrical signals and components connected to
that pin. For example, VOUT is the switch’s output pin, while VOUT is the electrical signal output voltage present at the
VOUT pin.
Pin Descriptions
Pin Name
Type
Description
VIN
Input
GND
─
ENABLE
Input
FAULT/
Output
CSLEW
Input
VOUT
Output
VUVLO
Input
Variable Under Voltage Lockout (VUVLO): Monitors the input voltage through a
resistor divider between VIN and GND. Shuts the switch off if voltage falls below the
threshold set by the resistor divider. Previously called VUVLO.
ILIMIT
Input
Set current limit threshold via a resistor connected from ILIMIT to GND.
Supply input. This pin provides power to both the output switch and the switch’s
internal control circuitry.
Ground.
Switch Enable (Input):
Fault status. A logic LOW on this pin indicates the switch is in current limiting, or has
been shut down by the thermal protection circuit. This is an open-drain output
allowing logical OR’ing of multiple switches.
Slew rate control. Adding a small value capacitor between this pin and VIN slows
turn-ON of the power FET.
Switch output. The load being driven by the switch is connected to this pin.
Signal Descriptions
Signal Name
Type
VIN
Input
GND
─
VEN
Input
Electrical signal input voltage present at the ENABLE pin.
VFAULT/
Output
Electrical signal output voltage present at the FAULT/ pin.
CSLEW
Component
VOUT
Output
Electrical signal output voltage present at the VOUT pin.
VVUVLO_TH
Internal
VUVLO internal reference threshold voltage. This voltage is compared to the
VUVLO pin input voltage to determine if the switch should be disabled. Reference
threshold voltage has a typical value of 250mV.
CLOAD
Component
IOUT
Output
Electrical signal output current present at the VOUT pin.
ILIMIT
Internal
Switch’s current limit. Fixed at factory or user adjustable.
January 2009
Description
Electrical signal input voltage present at the VIN pin.
Ground.
Capacitance value connected to the CSLEW pin.
Capacitance value connected in parallel with the load. Load capacitance.
9
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Absolute Maximum Ratings(1)
Operating Ratings(2)
VIN, VOUT.................................................. –0.3V to 6V
All other pins ............................................ –0.3V to 5.5V
Power Dissipation (PD) .......................Internally Limited
Continuous Output Current...................................2.25A
Continuous Output Current (MIC2005A) ................0.9A
Maximum Junction Temperature (TJ) .................. 150°C
Storage Temperature (Ts)...................–65°C to +150°C
Supply Voltage ..............................................2.5V to 5.5V
Continuous Output Current Range...................0A to 2.1A
Ambient Temperature Range (TA)............ –40°C to+85°C
(3)
Package Thermal Resistance
SOT-23-5/6 (θJA) .......................................... 230ºC/W
2mm x 2mm MLF-6 (θJA)................................ 90ºC/W
2mm x 2mm MLF-6 (θJC) ............................... 45ºC/W
Electrical Characteristics(4)
VIN = 5V, TA = 25°C unless otherwise specified. Bold indicates –40°C to +85°C limits; CIN = 1µF.
Symbol
Parameter
VIN
Switch Input Voltage
Condition
Min
Internal Supply Current
Switch = OFF
All except:
VEN = 0V
MIC2005-X.XLYM5
Switch = ON, IOUT = 0A
MIC2005A
VEN = 1.5V
Switch = OFF
Internal Supply Current
MIC2005-X.XLYM5
IIN
VEN = 1.5V
Switch = ON, IOUT = 0A
VEN = 0V
Switch = OFF
MIC2005A-1, VEN = 0V
Internal Supply Current
MIC2005A
Typ
Max
Units
5.5
V
1
5
µA
80
330
µA
8
15
µA
80
300
µA
1
5
µA
8
15
µA
80
300
µA
12
100
µA
1
5
2.5
Switch = OFF
MIC2005A-2, VEN = 1.5V
Switch = ON
MIC2005A-1, VEN = 1.5V
MIC2005A-2, VEN = 0V
Switch = OFF, VOUT = 0V
ILEAK
Output Leakage Current
Active Low; ENABLE = 1.5V
Active High; ENABLE = 0V
IEN
Enable Input Current
0V ≤ VEN ≤ 5V
ICSLEW
CSLEW Input Current
0V ≤ VOUT ≤ 0.8VIN
Power Switch Resistance
RDS(ON)
All except MIC2005A
Power Switch Resistance
Only MIC2005A
RDSCHG
ILIMIT
Load Discharge Resistance
MIC20X4 & MIC20X7
Fixed Current Limit
MIC20X3 – MIC20X6
January 2009
0.175
70
VIN = 5V, IOUT = 100mA
100
125
170
VIN = 5V, IOUT = 100mA
220
mΩ
275
VIN = 5V, ISINK = 5mA
70
MIC20XX-0.5, VOUT = 0.8 * VIN
0.5
0.7
0.9
MIC20XX-0.8, VOUT = 0.8 * VIN
0.8
1.1
1.5
MIC20XX-1.2, VOUT = 0.8 * VIN
1.2
1.6
2.1
10
µA
µA
126
200
Ω
A
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Electrical Characteristics (continued)
Symbol
CLF
ILIMIT_2nd
UVLOTHRESHOLD
UVLOHysteresis
VVUVLO_TH
Parameter
Condition
Min
Typ
Max
Variable Current Limit Factor
MIC20X7 – MIC20X9
IOUT = 2A, VOUT = 0.8VIN
210
250
286
IOUT = 1A, VOUT = 0.8VIN
190
243
293
RSET (Ω) = CLF (V)
IOUT (A)
IOUT = 0.5A, VOUT = 0.8VIN
168
235
298
IOUT = 0.2A, VOUT = 0.8VIN
144
225
299
VIN = 2.5V
2.2
4
6
VIN Rising
2
2.25
2.5
VIN Falling
1.9
2.15
2.4
Secondary current limit
MIC201X (All Kickstart parts only)
Under Voltage Lock Out Threshold
Undervoltage Lock Out
Hysteresis
0.1
Variable UVLO Threshold
225
MIC20X6
(5)
VEN
ENABLE Input Voltage
VFAULT
Fault status Output Voltage
OTTHRESHOLD
Over-temperature Threshold
250
VIL (MAX)
VIH (MIN)
275
1.5
0.25
TJ Increasing
145
TJ Decreasing
135
V
A
V
V
0.5
IOL = 10mA
Units
0.4
mV
V
V
°C
AC Characteristics
Symbol
Parameter
tRISE
Output Turn-on rise time
Condition
Min
Typ
Max
Units
500
1000
1500
µs
20
32
49
RL = 10 Ω, CLOAD = 1µF,
VOUT = 10% to 90%
*CSLEW = Open
Delay before asserting or releasing
FAULT/
MIC200X
tD_FAULT
Delay before asserting or releasing
FAULT/
MIC201X
tD_LIMIT
tRESET
Time from current limiting to
FAULT/ state change
Time from IOUT continuously
exceeding primary current
limit condition to FAULT/
state change
Delay before current limiting
MIC201X
Delay before resetting Kickstart
current limit delay, tD_LIMIT
MIC201X
Out of current limit following a
current limit event.
ms
77
128
192
77
128
192
ms
77
128
192
ms
1000
1500
µs
700
µs
RL = 43Ω, CL = 120µF,
tON_DLY
Output Turn-on Delay
VEN = 50% to VOUT = 10%
*CSLEW = Open
RL = 43Ω, CL = 120µF,
tOFF_DLY
Output Turn-off Delay
VEN = 50% to VOUT = 90%
*CSLEW = Open
Note: * Whenever CSLEW is present.
January 2009
11
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Electrical Characteristics (continued)
ESD
(6)
Symbol
Parameter
VESD_HB
Electro Static Discharge Voltage:
Human Body Model
VESD_MCHN
Condition
Min
VOUT and GND
±4
All other pins
±2
Typ
Max
Units
kV
All pins
Electro Static Discharge Voltage;
Machine Model
±200
Machine Model
V
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Requires proper thermal mounting to achieve this performance
4. Specifications for packaged product only.
5. VIL (MAX) = maximum positive voltage applied to the input which will be accepted by the device as a logic low.
VIH (MIN) = minimum positive voltage applied to the input which will be accepted by the device as a logic high.
6. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
Timing Diagrams
tFALL
tRISE
90%
90%
10%
10%
Rise and Fall Times
ENABLE
50%
50%
tON_DLY
tOFF_DLY
90%
VOUT
10%
Switching Delay Times
January 2009
12
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Typical Characteristics
16
25°C
SUPPLY CURRENT (µA)
-40°C
80
85°C
60
40
20
0
2
3
4
VIN (V)
5
2
3
1.40
4
VIN (V)
5
25°C
6
1.00
5V
3V
2.5V
1.06
0.80
0.60
0.20
3V
Note:
Please note that the 3
plots overlay each
V FALLING
5V
0.98
2.5V
120
100
60
40
20
2.1
January 2009
1.00
150
0
2
90
RON vs.
80
2.2
0
50
100
TEMPERATURE (°C)
1.02
0.96
-50 -30 -10 10 30 50 70
TEMPERATURE (°C)
90
Supply Voltage
100
(MIC20xx - 0.5)
1.04
RON vs.
V RISING
2.15
1.00
5V
90
ILIMIT vs. Temperature
1.10
0.00
-50 -30 -10 10 30 50 70
TEMPERATURE (°C)
UVLO Threshold
vs. Temperature
2.25
0.60
0.40
0.20
1.08
0.40
Switch Leakage Current
OFF
1.40
1.20
1.00
0.80
1.20
2.5V
90
2.00
1.80
1.60
0.00
-50 -30 -10 10 30 50 70
TEMPERATURE (°C)
ILIMIT (A)
ILIMIT (A)
1.02
RON (mOhm)
ILIMIT (A)
4
(MIC20xx - 0.8)
0.94
-50 -30 -10 10 30 50 70
TEMPERATURE (°C)
THRESHOLD (V)
85°C
6
ILIMIT vs. Temperature
1.04
2.05
-50
8
(MIC20xx - 1.2)
1.06
2.3
10
0
2
6
1.08
0.96
-40°C
12
ILIMIT vs. Temperature
1.10
0.98
14
RON (mOhm)
SUPPLY CURRENT (µA)
100
Supply Current
Output Disabled
LEAKAGE CURRENT (µA)
Supply Current
Output Enabled
Temperature
3.3V
2.5V
80
5V
60
40
20
2.5
3
3.5 4 4.5
VIN (V)
13
5
5.5
0
-50 -30 -10 10 30 50 70
TEMPERATURE (°C)
90
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Functional Characteristics
January 2009
14
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Functional Characteristics (continued)
January 2009
15
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Functional Diagram
VUVLO
MIC20X6
ENABLE
MIC20X4 - MIC20X9
FAULT/
MIC20X5 & MIC20X9
VUVLO
Under
Voltage
Detector
VIN
Current
Mirror FET
Control Logic
and
Delay Timer
Power FET
Gate Control
Load Discharge
MIC20X4 & MIC20X7
Thermal
Sensor
CSLEW
MIC20X5 - MIC20X8
VOUT
Slew Rate
Control
VREF
Current Limit
Control Loop
GND
ILIM Factory Adjusted
MIC20X3 - MIC20X6
ILIM
User Adjustable
MIC20X7 - MIC20X9
Figure 2 MIC20XX Family Functional Diagram
January 2009
16
M9999-012109-A
Micrel, Inc.
MIC20XX Family
of Kickstart operation is shown below.
Functional Description
VIN and VOUT
VIN is both the power supply connection for the internal
circuitry driving the switch and the input (Source
connection) of the power MOSFET switch. VOUT is the
Drain connection of the power MOSFET and supplies
power to the load. In a typical circuit, current flows from
VIN to VOUT toward the load. Since the switch is bidirectional when enabled, if VOUT is greater than VIN,
current will flow from VOUT to VIN.
When the switch is disabled, current will not flow to the
load, except for a small unavoidable leakage current of
a few microamps. However, should VOUT exceed VIN by
more than a diode drop (~0.6 V), while the switch is
disabled, current will flow from output to input via the
power MOSFET’s body diode.
If discharging CLOAD is required by your application,
consider using MIC20X4 or MIC20X7; these MIC20XX
family members are equipped with a discharge FET to
insure complete discharge of CLOAD.
Figure 3. Kickstart Operation
Figure 3 Label Key:
A) MIC201X is enabled into an excessive load (slew
rate limiting not visible at this time scale) The initial
current surge is limited by either the overall circuit
resistance and power supply compliance, or the
secondary current limit, whichever is less.
B) RON of the power FET increases due to internal
heating (effect exaggerated for emphasis).
C) Kickstart period.
D) Current limiting initiated. FAULT/ goes LOW.
E) VOUT is non-zero (load is heavy, but not a dead short
where VOUT = 0V. Limiting response will be the
same for dead shorts).
F) Thermal shutdown followed by thermal cycling.
G) Excessive load released, normal load remains.
MIC201X drops out of current limiting.
H) FAULT/ delay period followed by FAULT/ going
HIGH.
Current Sensing and Limiting
MIC20XX protects the system power supply and load
from damage by continuously monitoring current
through the on-chip power MOSFET. Load current is
monitored by means of a current mirror in parallel with
the power MOSFET switch. Current limiting is invoked
when the load exceeds the set over-current threshold.
When current limiting is activated the output current is
constrained to the limit value, and remains at this level
until either the load/fault is removed, the load’s current
requirement drops below the limiting value, or the switch
goes into thermal shutdown.
Kickstart
2003
2004
2005
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
Only parts in white boxes have Kickstart.
(Not available in 5-pin SOT-23 packages)
Under Voltage Lock Out
Under voltage lock-out insures no anomalous operation
occurs before the device’s minimum input voltage of
UVLOTHRESHOLD which is 2V minimum, 2.25V typical, and
2.5V maximum had been achieved. Prior to reaching
this voltage, the output switch (power MOSFET) is OFF
and no circuit functions, such as FAULT/ or ENABLE,
are considered to be valid or operative.
The MIC201X is designed to allow momentary current
surges (Kickstart) before the onset of current limiting,
which permits dynamic loads, such as small disk drives
or portable printers to draw the energy needed to
overcome inertial loads without sacrificing system
safety. In this respect, the Kickstart parts (MIC201X)
differs markedly from the non-Kickstart parts (MIC200X)
which immediately limit load current, potentially starving
the motor and causing the appliance to stall or stutter.
During this delay period, typically 128ms, a secondary
current limit is in effect. If the load demands a current in
excess the secondary limit, MIC201X acts immediately
to restrict output current to the secondary limit for the
duration of the Kickstart period. After this time the
MIC201X reverts to its normal current limit. An example
January 2009
17
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Because FAULT/ is an open-drain it must be pulled
HIGH with an external resistor 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 VIN, but no greater than 5.5V.
Variable Under Voltage Lock Out (VUVLO)
2003
2004
2005
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
Only parts in white boxes have VUVLO.
VUVLO functions as an input voltage monitor when the
switch in enabled. The VIN pin is monitored for a drop in
voltage, indicating excessive loading of the VIN supply.
When VIN is less than the VULVO threshold voltage
(VVUVLO_TH) for 32ms or more, the MIC20XX disables the
switch to protect the supply and allow VIN to recover.
After 128ms has elapsed, the MIC20X6 enables switch.
This disable and enable cycling will continue as long as
VIN deceases below the VUVLO threshold voltage
(VVUVLO_TH) which has a typical value of 250mV. The
VUVLO voltage is commonly established by a voltage
divider from VIN to GND.
Soft-start Control
Large capacitive loads can create significant inrush
current surges when charged through the switch. For
this reason, the MIC20XX family of switches provides a
built-in soft-start control to limit the initial inrush currents.
Soft-start is accomplished by controlling the power
MOSFET when the ENABLE pin enables the switch.
CSLEW
2004
2005
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
ENABLE pin is a logic compatible input which activates
the main MOSFET switch thereby providing power to
the VOUT pin. ENABLE is either an active HIGH or active
LOW control signal. The MIC20XX can operate with
logic running from supply voltages as low as 1.8V.
ENABLE may be driven higher than VIN, but no higher
than 5.5V and not less than –0.3V.
2004
2005
2006
2007
2008
2009
2014
2015
2016
2017
2018
2019
Only parts in white boxes have FAULT/ pin.
FAULT/ is an N-channel open-drain output, which is
asserted (LOW true) when switch either begins current
limiting or enters thermal shutdown.
FAULT/ asserts after a brief delay when events occur
that may be considered possible faults. This delay
insures that FAULT/ is asserted only upon valid,
enduring, over-current conditions and that transitory
event error reports are filtered out.
In MIC200X FAULT/ asserts after a brief delay period, of
32ms typical. After a fault clears, FAULT/ remains
asserted for the delay period of 32ms
MIC201X’s FAULT/ asserts at the end of the Kickstart
period which is 128ms typical. 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 the
FAULT/ will be asserted. After a fault clears, FAULT/
remains asserted for the delay of 128ms.
January 2009
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
Thermal Shutdown
Thermal shutdown is employed to protect the MIC20XX
family of switches 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 switch will automatically resume operation when the
die temperature cools down to 135°C. If resumed
operation results in reheating of the die, another
shutdown cycle will occur and the switch will continue
cycling between ON and OFF states until the
overcurrent condition has been resolved.
Depending on 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.
FAULT/
2013
2005
The CSLEW pin is provided to increase control of the
output voltage ramp at turn-on. This input allows
designers the option of decreasing the output’s slew rate
(slowing the voltage rise) by adding an external
capacitance between the CSLEW and VIN pins.
Only parts in white boxes have ENABLE pin.
2003
2004
Only parts in white boxes have CSLEW pin.
(Not available in 5-pin SOT-23 packages)
ENABLE
2003
2003
18
M9999-012109-A
Micrel, Inc.
MIC20XX Family
ILIMIT vs. IOUT measured
The MIC20XX’s current limiting circuitry, during current
limiting, is designed to act as a constant current source
to the load. As the load tries to pull more than the
allotted current, VOUT drops and the input to output
voltage differential increases. When VIN - VOUT exceeds
1V, IOUT drops below ILIMIT to reduce the drain of fault
current on the system’s power supply and to limit
internal heating of the switch.
When measuring IOUT it is important to bear this voltage
dependence in mind, otherwise the measurement data
may appear to indicate a problem when none really
exists. This voltage dependence is illustrated in Figures
4 and 5.
In Figure 4 output current is measured as VOUT is pulled
below VIN, with the test terminating when VOUT is 1V
below VIN. Observe that once ILIMIT is reached IOUT
remains constant throughout the remainder of the test.
In Figure 5 this test is repeated but with VIN - VOUT
exceeding 1V.
When VIN - VOUT > 1V, switch’s current limiting circuitry
responds by decreasing IOUT, as can be seen in Figure
5. In this demonstration, VOUT is being controlled and
IOUT is the measured quantity. In real life applications
VOUT is determined in accordance with Ohm’s law by the
load and the limiting current.
Application Information
Setting ILIMIT
The MIC2009/2019’s current limit is user programmable
and controlled by a resistor connected between the ILIMIT
pin and Ground. The value of this resistor is determined
by the following equation:
ILIMIT =
CurrentLim itFactor(CLF)
R SET
R SET =
CurrentLim itFactor(V)
ILIMIT (A)
or
For example: Set ILIMIT = 1.25 A
Looking in the Electrical specifications we will find CLF
at ILIMIT = 1 A.
Min
Typ
Max
Units
190
243
293
V
For the sake of this example, we will say the typical
value of CLF at an IOUT of 1A is 243V. Applying the
equation above:
R SET (Ω) =
243V
= 194.4Ω
1.25A
RSET = 196Ω
(the closest standard 1% value)
Designers should be aware that variations in the
measured ILIMIT for a given RSET resistor, will occur
because of small differences between individual ICs
(inherent in silicon processing) resulting in a spread of
ILIMIT values. In the example above we used the typical
value of CLF to calculate RSET. We can determine ILIMIT’s
spread by using the minimum and maximum values of
CLF and the calculated value of RSET.
ILIMIT_MIN =
190V
= 0.97 A
196Ω
ILIMIT_MIN =
260V
= 1.5 A
196Ω
Figure 4. IOUT in Current Limiting for VIN
- VOUT < 1V
Giving us a maximum ILIMIT variation over temperature
of:
ILIMIT_MIN
ILIMIT_TYP
ILIMIT_MAX
0.97 A
1.25 A
1.5 A
or
1.25 A – 22%
and
1.25 A + 20%
January 2009
19
M9999-012109-A
Micrel, Inc.
MIC20XX Family
CSLEW
2003
2004
2005
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
Only parts in white boxes have CSLEW pin.
(Not available in 5-pin SOT-23 packages).
The CSLEW pin is provided to increase control of the
output voltage ramp at turn-on. This input allows
designers the option of decreasing the output’s slew rate
(slowing the voltage rise) by adding an external
capacitance between the CSLEW and VIN pins. This
capacitance slows the rate at which the pass FET gate
voltage increases and thus, slows both the response to
an Enable command as well as VOUT’s ascent to its final
value.
Figure 8 illustrates effect of CSLEW on turn-on delay and
output rise time.
- VOUT > 1V
Figure 5. IOUT in Current Limiting for VIN
Typical Turn-on Times
Capacitance
vs. External C
NORMALIZED OUTPUT CURRENT (A)
0.0088
6
0.006
4
0.004
1.0
2
0.002
0.8
0
TRISE
0
4 4.5
2 2.5
3 3.5
0 0.5
0 1
0 1.5
0 0
0 0
0 0
0
CSLEW (nF)
0.6
0.4
Figure 8.
0.2
0
1.2
TDELAY
10
0.01
0
1
2
3
4
5
OUTPUT VOLTAGE (V)
CSLEW’s effect on ILIMIT
An unavoidable consequence of adding CSLEW
capacitance is a reduction in the MIC20X5 – 20X8’s
ability to quickly limit current transients or surges. A
sufficiently large capacitance can prevent both the
primary and secondary current limits from acting in time
to prevent damage to the MIC20X5 – 20X8 or the
system from a short circuit fault. For this reason, the
upper limit on the value of CSLEW is 4nF.
6
Figure 6.
Normalized Output Current
vs. Output Voltage (2.5V)
1.0
Variable Under Voltage Lock Out (VUVLO)
0.8
2003
2004
2005
2006
2007
2008
2009
0.6
2013
2014
2015
2016
2017
2018
2019
Only parts in white boxes have VUVLO pin and functionality.
0.4
Power conscious systems, such as those implementing
ACPI, will remain active even in their low power states
and may require the support of external devices through
both phases of operation. Under these conditions, the
current allowed these external devices may vary
according to the system’s operating state and as such
0.2
0
0
0.5 1.0 1.5 2.0 2.5
OUTPUT VOLTAGE (V)
3.0
Figure 7.
January 2009
TON
12
0.012
Normalized Output Current
vs. Output Voltage (5V)
1.2
SLEW
14
0.014
TIME (mS)
NORMALIZED OUTPUT CURRENT (A)
This folding back of ILIMIT can be generalized by plotting
ILIMIT as a function of VOUT, as shown below in Figures 6
and 7. The slope of VOUT between IOUT = 0V and IOUT =
ILIMIT (where ILIMIT = 1A) is determined by RON of the
switch and ILIMIT.
20
M9999-012109-A
Micrel, Inc.
MIC20XX Family
VUVLO and Kickstart operate independently in the
MIC2016. If the high current surge allowed by Kickstart
causes VIN to dip below the VUVLO trip point for more
than 32ms, VUVLO will disengage the load even though
the Kickstart timer has not timed out.
require dual current limits on their peripheral ports. The
MIC20X6 is designed for systems demanding two
primary current limiting levels but without the use of a
control signal to select between current limits.
To better understand how the MIC20X6 provides this,
imagine a system whose main power supply supports
heavy loads during normal operation, but in sleep mode
is reduced to only few hundred milliamps of output
current. In addition, this system has several USB ports
which must remain active during sleep. In normal
operation, each port can support a 500mA peripheral,
but in sleep mode their combined output current is
limited to what the power supply can deliver minus
whatever the system itself is drawing.
If a peripheral device is plugged in which demands more
current than is available, the system power supply will
sag, or crash. The MIC20X6 prevents this by monitoring
both the load current and VIN. During normal operation,
when the power supply can source plenty of current, the
MIC20X6 will support any load up to its factory
programmed current limit. When the weaker, standby
supply is in operation, the MIC20X6 monitors VIN and
will shut off its output should VIN dip below a
predetermined value. This predetermined voltage is user
programmable and set by the selection of the resistor
divider driving the VUVLO pin.
To prevent false triggering of the VUVLO feature, the
MIC20X6 includes a delay timer to blank out momentary
excursions below the VUVLO trip point. If VIN stays
below the VUVLO trip point for longer than 32ms
(typical), then the load is disengaged and the MIC20X6
will wait 128ms before reapplying power to the load. If
VIN remains below the VUVLO trip point, then the load
will be powered for the 32ms blanking period and then
again disengaged. This is illustrated in the scope plot
below. If VIN remains above the VUVLO trip point
MIC20X6 resumes normal operation.
IIN_LOAD
Input
Supply
VIN
VOUT
R1
+
+
VUVLO
R2
Calculating VUVLO resistor divider values
Selection of R1 and R2 is driven by the input voltage at
which VUVLO should go into effect and the allowed
loading of the input supply. The VUVLO pin input
voltage is the result of the voltage division of VIN by the
voltage divider comprised of R1 and R2. We know
VVUVLO_TH = 250 mV, then by choosing a VIN trip voltage
(VTRIP) we know the voltage divider ratio formed by R1
and Then an R2.is chosen such that the series
resistance R1 + R2 results in a small IIN_LOAD.
And then the VUVLO trip voltage as it relates to the
comparator threshold and the resistor divider:
VVUVLO_TH
VTRIP
=
R2
=X
(R 2 + R1 )
Rearranging these:
R1 =
X
*R
(1 − X ) 2
Choose an R2 that minimizes the IIN_LOAD current yet at
the same time is less than input impedance of the
VUVLO pin. The VUVLO pin internally is connected to a
comparator with an extremely high input impedance. It is
recommended that R2 not exceed 1 MΩ. R2 can then be
calculated from the equation above.
For example:
VTRIP = 4.75V for a 5V supply
VVUVLO_TH = 250mV
R2 = 750kΩ
Substituting these values into the equation above:
X =
R1 =
VTRIP
0.05263
=
4.75 V
= 0.05263
0.25 V
(1 − 0.05263 )
* 750 kΩ = 41,667kΩ
R1 = 41,667kΩ
Figure 9. VUVLO Operation
January 2009
VVUVLO_TH
21
M9999-012109-A
Micrel, Inc.
MIC20XX Family
In this example we have used the nominal value of
VVUVLO_TH. By substituting in the min and max values of
VVUVLO_TH, R1 and R2 the VUVLO trip point window can
be established.
The VUVLO comparator uses no Hysteresis. This is
because the VUVLO blanking timer prevents any
chattering that might otherwise occur if VIN varies about
the trigger point. The timer is reset by upward crossings
of the trip point such that VIN must remain below the trip
point for the full 32ms period for load disengagement to
occur.
In selecting a VTRIP voltage the designer is cautioned to
not make this value less than 2.5V. A minimum of 2.5V
is required for the MIC20X6’s internal circuitry to operate
properly. VUVLO trip points below 2.5V will result in
erratic or unpredictable operation.
Figure 10. Kickstart
Kickstart
2003
2004
2005
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
Automatic Load Discharge
Only parts in white boxes have Kickstart.
(Not available in 5-pin SOT-23 packages).
2004
2005
2006
2007
2008
2009
2013
2014
2015
2016
2017
2018
2019
Only parts in white boxes have automatic load discharge.
Kickstart allows brief current surges to pass to the load
before the onset of normal current limiting, which
permits dynamic loads to draw bursts of energy without
sacrificing system safety.
Functionally, Kickstart is a forced override of the normal
current limiting function provided by the switch. The
Kickstart period is governed by an internal timer which
allows current to pass up to the secondary current limit
(ILIMIT_2nd) to the load for 128ms and then normal
(primary) current limiting goes into action.
During Kickstart a secondary current limiting circuit is
monitoring output current to prevent damage to the
switch, as a hard short combined with a robust power
supply can result in currents of many tens of amperes.
This secondary current limit is nominally set at 4A and
reacts immediately and independently of the Kickstart
period. Once the Kickstart timer has finished its count
the primary current limiting circuit takes over and holds
IOUT to its programmed limit for as long as the excessive
load persists.
Once the switch drops out of current limiting the
Kickstart timer initiates a lock-out period of 128ms such
that no further bursts of current above the primary
current limit, will be allowed until the lock-out period has
expired.
Kickstart may be over-ridden by the thermal protection
circuit and if sufficient internal heating occurs, Kickstart
will be terminated and IOUT Æ 0A. Upon cooling, if the
load is still present IOUT Æ ILIMIT, not ILIMIT_2nd.
January 2009
2003
Automatic discharge is a valuable feature when it is
desirable to quickly remove charge from the VOUT pin.
This allows for a quicker power-down of the load. This
also prevents any charge from being presented to a
device being connected to the VOUT pin, for example,
USB, 1394, PCMCIA, and CableCARD™.
Automatic discharge is performed by a shunt MOSFET
from VOUT pin to GND. When the switch is disabled, a
break before make action is performed turning off the
main power MOSFET and then enabling the shunt
MOSFET. The total resistance of the MOSFET and
internal resistances is typically 126Ω.
Supply Filtering
A minimum 1μF bypass capacitor positioned close to
the VIN and GND pins of the switch is both good design
practice and required for proper operation of the switch.
This will control supply transients and ringing. Without a
bypass capacitor, large current surges or a short may
cause sufficient ringing on VIN (from supply lead
inductance) to cause erratic operation of the switch’s
control circuitry. For best performance good quality, low
ESR capacitors are recommended, preferably ceramic.
When bypassing with capacitors of 10μF and up, it is
good practice to place a smaller value capacitor in
parallel with the larger to handle the high frequency
components of any line transients. Values in the range
of 0.01μF to 0.1μF are recommended. Again, good
quality, low ESR capacitors should be chosen.
22
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Power Dissipation
Power dissipation depends on several factors such as
the load, PCB layout, ambient temperature, and supply
voltage. Calculation of power dissipation can be
accomplished by the following equation:
Die Temperature vs.
Output Current (T CASE=85°C)
160
140
120
PD = R DS(ON) × (IOUT )
100
2
MLF
80
To relate this to junction temperature, the following
equation can be used:
60
40
TJ = PD × Rθ (J- A) + TA
20
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
OUTPUT CURRENT (A)
Where: TJ = junction temperature,
TA = ambient temperature
Rθ(J-A) is the thermal resistance of the package
In normal operation the switch’s Ron is low enough that
2
no significant I R heating occurs. Device heating is most
often caused by a short circuit, or very heavy load, when
a significant portion of the input supply voltage appears
across the switch’s power MOSFET. Under these
conditions the heat generated will exceed the package
and PCB’s ability to cool the device and thermal limiting
will be invoked.
In Figure 11 die temperature is plotted against IOUT
assuming a constant case temperature of 85°C. The
plots also assume a worst case RON of 140mΩ at a die
temperature of 135°C. Under these conditions it is clear
that an SOT-23 packaged device will be on the verge of
thermal shutdown, typically 140°C die temperature,
when operating at a load current of 1.25A. For this
®
reason we recommend using MLF packaged switch s
for any design intending to supply continuous currents of
1A or more.
January 2009
SOT-23
Figure 11. Die Temperature vs. IOUT
23
M9999-012109-A
Micrel, Inc.
MIC20XX Family
Package Information
5-Pin SOT-23 (M5)
6-Pin SOT-23 (M6)
January 2009
24
M9999-012109-A
Micrel, Inc.
MIC20XX Family
®
6 Pin 2mm x 2mm MLF (ML)
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its
use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant
into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
© 2008 Micrel, Incorporated.
January 2009
25
M9999-012109-A
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