MIC20XX [MICREL]
Fixed and Adjustable Current Limiting Power Distribution Switches; 固定和可调电流限制配电开关![MIC20XX](http://pdffile.icpdf.com/pdf1/p00179/img/icpdf/MIC20_1009157_icpdf.jpg)
型号: | MIC20XX |
厂家: | ![]() |
描述: | Fixed and Adjustable Current Limiting Power Distribution Switches |
文件: | 总29页 (文件大小:1277K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
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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 8.
• MIC20X3 – MIC20X9
70mΩ typical on-resistance @ 5V
• MIC2005A/20X9A
170mΩ typical on-resistance @ 5V
• Enable active high or active low
• 2.5V – 5.5V operating range
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
• Pre-set current limit values of 0.5A, 0.8A, and 1.2A*
• Adjustable current limit 0.2A to 2.0A* (MIC20X7-
MIC20X9)
• Adjustable current limit 0.1A to 0.9A* (MIC20X9A)
• Under voltage lock-out (UVLO)
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.
• 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
The MIC201X (3 ≤ x ≤ 9) and MIC2019A switches offer 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.
• Thermal Protection
* Available on some family members
Applications
• Digital televisions (DTV)
• Set top boxes
• PDAs
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.
• Printers
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
• USB / IEEE 1394 power distribution
• Desktop and laptop PCs
• Game consoles
• Docking stations
___________________________________________________________________________________________________________
Typical Application
5V Supply
MIC2005A
Logic
VBUS
120µF
Controller
VIN
GND
EN
VOUT
USB
Port
VIN
FAULT/
ON/OFF
1µF
OVERCURRENT/
Figure 1. Typical Application Circuit
Kickstart is a trademark of Micrel, Inc.
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Protected by U.S. Patent No. 7,170,732
CableCARD is a trademark of CableLabs.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
M9999-020311-D
February 2011
Micrel, Inc.
MIC20xx Family
Ordering Information
MIC2003/2013
Part Number(1)
Marking(2)
FD05
Current Limit
0.5A
Kickstart™ Package
MIC2003-0.5YM5
MIC2003-0.8YM5
MIC2003-1.2YM5
MIC2003-0.5YML
MIC2003-0.8YML
MIC2003-1.2YML
MIC2013-0.5YM5
MIC2013-0.8YM5
MIC2013-1.2YM5
MIC2013-0.5YML
MIC2013-0.8YML
MIC2013-1.2YML
5-Pin SOT-23
FD08
FD12
0.8A
1.2A
No
0.5A
D05
D08
6-Pin 2mm x 2mm MLF®
0.8A
1.2A
D12
FL05
0.5A
5-Pin SOT-23
FL08
FL12
0.8A
1.2A
Yes
0.5A
L05
L09
L12
6-Pin 2mm x 2mm MLF®
0.8A
1.2A
MIC2004/2014
Part Number(1)
Marking(2)
Current Limit
0.5A
Kickstart™ Package
MIC2004-0.5YM5
MIC2004-0.8YM5
MIC2004-1.2YM5
MIC2004-0.5YML
MIC2004-0.8YML
MIC2004-1.2YML
MIC2014-0.5YM5
MIC2014-0.8YM5
MIC2014-1.2YM5
MIC2014-0.5YML
MIC2014-0.8YML
FE05
FE08
FE12
5-Pin SOT-23
0.8A
1.2A
No
0.5A
E05
E08
6-Pin 2mm x 2mm MLF®
5-Pin SOT-23
0.8A
1.2A
E12
FM05
0.5A
FM08
FM12
0.8A
1.2A
Yes
0.5A
M05
M09
M12
6-Pin 2mm x 2mm MLF®
0.8A
MIC2014-1.2YML
1.2A
Notes:
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.
February 2011
2
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Ordering Information (continued)
MIC2005
Part Number(1)
MIC2005-0.5YM6
MIC2005-0.8YM6
MIC2005-1.2YM6
MIC2005-0.5YML
MIC2005-0.8YML
MIC2005-1.2YML
Marking(2)
FF05
Current Limit
0.5A
Enable
Active High
Kickstart™ Package
6-Pin SOT-23
FF08
FF12
0.8A
Active High
Active High
Active High
Active High
Active High
1.2A
No
0.5A
F05
F08
F12
6-Pin 2mm x 2mm MLF®
0.8A
1.2A
MIC2005L
Part Number(1)
Marking(2)
Current Limit
0.5A
Enable
Kickstart™ Package
MIC2005-0.5LYM5
MIC2005-0.8LYM5
MIC2005-1.2LYM5
5LFF
8LFF
4LFF
Active Low
Active Low
Active Low
No
5-Pin SOT-23
0.8A
1.2A
MIC2005A
Part Number(1)
MIC2005A-1YM5
MIC2005A-2YM5
MIC2005A-1YM6
MIC2005A-2YM6
Marking(2)
Current Limit
0.5A
Enable
Kickstart™ Package
FA51
FA52
FA53
FA54
Active High
Active Low
Active High
Active Low
5-Pin SOT-23
0.5A
No
0.5A
6-Pin SOT-23
0.5A
MIC2015
Part Number(1)
MIC2015-0.5YM6
MIC2015-0.8YM6
MIC2015-1.2YM6
MIC2015-0.5YML
MIC2015-0.8YML
Marking(2)
Current Limit
0.5A
Enable
Kickstart™ Package
FN05
FN08
FN12
Active High
Active High
Active High
Active High
Active High
Active High
6-Pin SOT-23
0.8A
1.2A
Yes
0.5A
N05
N08
N12
6-Pin 2mm x 2mm MLF®
0.8A
MIC2015-1.2YML
1.2A
Notes:
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.
February 2011
3
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Ordering Information (continued)
MIC2006/2016
Part Number(1)
MIC2006-0.5YM6
MIC2006-0.8YM6
MIC2006-1.2YM6
MIC2006-0.5YML
MIC2006-0.8YML
MIC2006-1.2YML
MIC2016-0.5YM6
MIC2016-0.8YM6
MIC2016-1.2YM6
MIC2016-0.5YML
MIC2016-0.8YML
MIC2016-1.2YML
Marking(2)
FG05
Current Limit
0.5A
Kickstart™ Package
6-Pin SOT-23
FG08
FG12
0.8A
1.2A
No
0.5A
G05
G08
0.8A
6-Pin 2mm x 2mm MLF®
1.2A
G12
FP05
FP08
FP12
0.5A
6-Pin SOT-23
0.8A
1.2A
Yes
0.5A
P05
P09
P12
6-Pin 2mm x 2mm MLF®
0.8A
1.2A
MIC2007/2017
Part Number(1)
MIC2007YM6
MIC2007YML
MIC2017YM6
MIC2017YML
Marking(2)
Current Limit
Kickstart™ Package
FHAA
6-Pin SOT-23
6-Pin 2mm x 2mm MLF®
No
HAA
0.2A – 2.0A
FQAA
6-Pin SOT-23
6-Pin 2mm x 2mm MLF®
Yes
QAA
MIC2008/2018
Part Number(1)
MIC2008YM6
MIC2008YML
MIC2018YM6
MIC2018YML
Marking(2)
Current Limit
Kickstart™ Package
FJAA
6-Pin SOT-23
6-Pin 2mm x 2mm MLF®
No
JAA
0.2A – 2.0A
FRAA
6-Pin SOT-23
6-Pin 2mm x 2mm MLF®
Yes
RAA
MIC2009/2019
Part Number(1)
MIC2009YM6
MIC2009YML
Marking(2)
Current Limit
Kickstart™ Package
FKAA
6-Pin SOT-23
No
6-Pin 2mm x 2mm MLF®
KAA
0.2A – 2.0A
MIC2019YM6
MIC2019YML
FSAA
6-Pin SOT-23
Yes
6-Pin 2mm x 2mm MLF®
SAA
Notes:
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.
February 2011
4
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Ordering Information (continued)
MIC2009A/2019A
Part Number (1) Marking (2) Current Limit Kickstart™ Enable
Package
MIC2009A-1YM6
FK1
Active High
No
MIC2009A-2YM6
MIC2019A-1YM6
MIC2019A-2YM6
FK2
FS1
FS2
Active Low
Active High
Active Low
0.1 A – 0.9 A
6-pin SOT-23
Yes
Notes:
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.
February 2011
5
M9999-020311-D
Micrel, Inc.
MIC20xx Family
MIC20XX Family Member Functionality
Part Number
Pin Function
Normal
Limiting
ENABLE ENABLE
Load
Discharge
Kickstart™(1) I Limit
ILIMIT
High
Low
CSLEW FAULT/
VUVLO(5)
2003
2004
2013
–
–
–
–
─
–
–
─
▲
─
─
─
─
─
▲
─
─
─
─
2014
2015
─
─
▲
▲
─
─
─
─
─
─
─
─
─
▲
─
─
─
─
─
2005
▲
─
▲
▲
▲
▲
─
Fixed (2)
(1)
2005L
2005A-1
2005A-2
2006
─
─
▲
─
(1)
(6)
─
─
▲
─
─
─
(1)
(6)
─
─
▲
─
2016
2017
2018
─
▲
▲
▲
▲
▲
─
▲
2007
▲
▲
▲
▲
▲
─
▲
▲
─
─
2008
─
─
Adj.(3)
2019
2009
─
▲
▲
▲
2009A-1
2019A-1
2019A-2
─
─
2009A-2
▲
─
Notes:
1.
2.
3.
4.
5.
6.
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, SOT Packages
Part Number
Pin Number
4
Normal Limiting
Kickstart™
I Limit
1
2
3
5
6
2003
2004
2013
VIN
GND
NC
─
NC
VOUT
VOUT
CSLEW
VOUT
2014
2015
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
EN
EN
EN
EN
EN
EN
EN
EN
EN
EN
─
NC
2005
FAULT/
FAULT/
FAULT/
FAULT/
VUVLO(4)
ILIMIT
VOUT
─
Fixed(2)
(1)
2005L
2005Axxx6
2005Axxx5
2006
─
(1)
─
CSLEW
VOUT
VOUT
─
(1)
─
2016
2017
2018
2019
2019A
CSLEW
VOUT
VOUT
VOUT
VOUT
VOUT
2007
CSLEW
CSLEW
ILIMIT
2008
ILIMIT
Adj.(3)
2009
FAULT/
FAULT/
2009A
ILIMIT
Notes:
1.
2.
Kickstart™ not available.
Fixed = Factory programmed current limit.
February 2011
6
M9999-020311-D
Micrel, Inc.
MIC20xx Family
3.
4.
ILIMIT = User adjustable current limit.
VUVLO = Variable UVLO (Previously called DLM).
MIC20XX Family Member Pin Configuration Table, MLF Packages (5)
Part Number
Pin Number
3
Normal Limiting
Kickstart™
I Limit
6
5
4
2
1
2003
2004
2005
2006
2007
2008
2013
VIN
GND
NC
NC
NC
NC
VOUT
VOUT
VOUT
VOUT
2014
2015
2016
2017
2018
2019
VIN
VIN
VIN
VIN
VIN
VIN
GND
GND
GND
GND
GND
GND
EN
EN
EN
EN
EN
EN
NC
Fixed(2)
FAULT/
VUVLO(4)
ILIMIT
ILIMIT
FAULT/
CSLEW
CSLEW
CSLEW
CSLEW
ILIMIT
VOUT
VOUT
VOUT
Adj.(3)
2009
Notes:
1.
2.
3.
4.
5.
Kickstart™ not available.
Fixed = Factory programmed current limit.
LIMIT = User adjustable current limit.
I
VUVLO = Variable UVLO (Previously called DLM).
Connect EP to GND.
February 2011
7
M9999-020311-D
Micrel, Inc.
MIC20xx Family
MIC20XX Family Member Pin Configuration Drawings
Fixed Current Limit
MIC20X3
VIN
GND
NC
1
2
3
VOUT
NC
5
4
5-Pin SOT-23 (M5)
6-Pin MLF® (ML)
(Top View)
MIC20X4
VIN
GND
1
2
3
VOUT
NC
5
4
ENABLE
5-Pin SOT-23 (M5)
6-Pin MLF® (ML)
(Top View)
MIC20X5
VIN
VIN
GND
1
2
3
VOUT
1
2
3
5
4
VOUT
6
5
4
GND
CSLEW
FAULT/
ENABLE
ENABLE
FAULT/
5-Pin SOT-23 (M5)
MIC2005-X.XL
6-Pin SOT-23 (M6)
MIC20X5
6-Pin MLF® (ML)
(Top View)
MIC20X5
MIC20X6
VIN
GND
1
2
3
VOUT
6
5
4
CSLEW
VUVLO
ENABLE
6-Pin SOT-23 (M6)
6-Pin MLF® (ML)
(Top View)
February 2011
8
M9999-020311-D
Micrel, Inc.
MIC20xx Family
MIC20XX Family Member Pin Configuration Drawings (continued)
Adjustable Current Limit
MIC20X7/20X8
VIN
GND
1
2
3
VOUT
6
5
4
CSLEW
ILIMIT
ENABLE
6-Pin SOT-23 (M6)
6-Pin MLF® (ML)
(Top View)
MIC20X9
VIN
1
2
3
VOUT
ILIMIT
FAULT/
6
5
4
GND
ENABLE
6-Pin SOT-23 (M6)
6-Pin MLF® (ML)
(Top View)
MIC2005A
VIN
VIN
1
2
3
VOUT
1
2
3
5
4
VOUT
6
5
4
GND
GND
CSLEW
FAULT/
ENABLE
ENABLE
FAULT/
5-Pin SOT-23 (M5)
6-Pin SOT-23 (M6)
MIC2009A
VIN
GND
1
2
3
VOUT
ILIMIT
FAULT/
6
5
4
ENABLE
6-Pin SOT-23 (M6)
February 2011
9
M9999-020311-D
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
Supply input. This pin provides power to both the output switch and the switch’s internal
control circuitry.
VIN
Input
GND
EN
─
Ground.
Input
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.
FAULT/
Output
Slew rate control. Adding a small value capacitor between this pin and VIN slows turn-ON of
the power FET.
CSLEW
VOUT
Input
Output
Switch output. The load being driven by the switch is connected to this pin.
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.
VUVLO
Input
ILIMIT
EP
Input
Set current limit threshold via a resistor connected from ILIMIT to GND.
On MLF packages connect EP to GND.
Thermal
Signal Descriptions
Signal Name
VIN
Type
Description
Input
─
Electrical signal input voltage present at the VIN pin.
Ground.
GND
VEN
Input
Electrical signal input voltage present at the ENABLE pin.
Electrical signal output voltage present at the FAULT/ pin.
Capacitance value connected to the CSLEW pin.
Electrical signal output voltage present at the VOUT pin.
VFAULT/
CSLEW
VOUT
Output
Component
Output
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.
VVUVLO_TH
Internal
CLOAD
IOUT
Component
Output
Capacitance value connected in parallel with the load. Load capacitance.
Electrical signal output current present at the VOUT pin.
ILIMIT
Internal
Switch’s current limit. Fixed at factory or user adjustable.
February 2011
10
M9999-020311-D
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
All except MIC2005A / MIC20X9A................. 2.25A
MIC2005A / 20X9A.......................................... 1.0A
Maximum Junction Temperature (TJ).................. 150°C
Storage Temperature (Ts) .................. –65°C to +150°C
Lead Temperature (Soldering 10 sec) ................ 260°C
Supply Voltage.............................................. 2.5V to 5.5V
Continuous Output Current
All except MIC2005A / MIC20X9A ........... 0A to 2.1A
MIC2005A/20X9A...................................... 0A to 0.9A
Ambient Temperature Range (TA) ............–40°C to+85°C
Package Thermal Resistance(3)
SOT-23-5/6 (θJA) ..........................................230ºC/W
2mm × 2mm MLF® (θJA) .................................90ºC/W
2mm × 2mm MLF® (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
Condition
Min
2.5
Typ
Max
5.5
Units
VIN
Switch Input Voltage
V
Switch = OFF, VOUT = 0V
Active Low Enable, VEN = 1.5V
Active High Enable, VEN = 0V
ILEAK
Output Leakage Current(5)
12
100
µA
µA
MIC2005A, MIC2009A, MIC2019A
Switch = ON
Active Low Enable, VEN = 0V
Active High Enable, VEN = 1.5V
80
8
300
IIN
Supply Current(5)
Switch = OFF
Active Low Enable, VEN = 1.5V
15
5
µA
µA
Switch = OFF
Active High Enable, VEN = 0V
1
170
220
mΩ
mΩ
RDS(ON)
Power Switch Resistance
Fixed Current Limit
VIN = 5V, IOUT = 100mA
VOUT = 0.8 × VIN
275
MIC2005A
ILIMIT
0.5
0.7
0.9
A
V
A
MIC2009A, MIC2019A
IOUT = 0.9A, VOUT = 0.8 × VIN
IOUT = 0.5A, VOUT = 0.8 × VIN
IOUT = 0.2A, VOUT = 0.8 × VIN
172
152
138
121
211
206
200
192
263
263
263
263
CLF
Variable Current Limit Factors
I
OUT = 0.1A, VOUT = 0.8 × VIN
MIC2019A
ILIMIT_2nd
Secondary Current Limit
VIN = 2.5V, VOUT = 0V
1
2
3
February 2011
11
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Symbol
MIC2003-MIC2009, MIC2013-MIC2019, MIC2005-X.XL
Switch = ON
Parameter
Condition
Min
Typ
Max
330
Units
Active Low Enable, VEN = 0V
Active High Enable, VEN = 1.5V
80
8
µA
IIN
Supply Current5
Switch = OFF
15
5
µA
µA
Active Low Enable, VEN = 1.5V
Switch = OFF
Active High Enable, VEN = 0V
1
70
100
mΩ
mΩ
RDS(ON)
Power Switch Resistance
VIN = 5V, IOUT = 100mA
125
MIC2003-X.X, MIC2004-X.X, MIC2005-X.X, MIC2006-X.X, MIC2013-X.X, MIC2014-X.X, MIC2015-X.X MIC2016-X.X, MIC2005-X.XL
-0.5, VOUT = 0.8 x VIN
-0.8, VOUT = 0.8 x VIN
-1.2, VOUT = 0.8 x VIN
0.5
0.8
1.2
0.7
1.1
1.6
0.9
1.5
2.1
ILIMIT
Fixed Current Limit
A
A
MIC2005-0.5
ILIMIT
Fixed Current Limit
VOUT = 0.8 x VIN
0.5
0.7
0.9
MIC2007, MIC2008, MIC2009, MIC2017, MIC2018, MIC2019
IOUT = 2.0A, VOUT = 0.8 x VIN
210
190
168
144
250
243
235
225
286
293
298
299
IOUT = 1.0A, VOUT = 0.8 x VIN
IOUT = 0.5A, VOUT = 0.8 x VIN
CLF
Variable Current Limit Factors
V
I
OUT = 0.2A, VOUT = 0.8 x VIN
MIC2013, MIC2014, MIC2015, MIC2016, MIC2017, MIC2018, MIC2019
ILIMIT_2nd
Secondary Current Limit
VIN = 2.5V, VOUT = 0V
2.2
225
70
4
6
A
mV
Ω
MIC2006, MIC2016
VUVLO_TH
Variable UVLO Threshold
250
275
200
MIC20x4, MIC20x7
RDSCHG
Load Discharge Resistance
VIN = 5V, ISINK = 5mA
0V ≤ VOUT ≤ 0.8VIN
VIL (MAX)
126
MIC20X5, MIC20X6, MIC20X7, MIC20X8
ICSLEW
CSLEW Input Current
0.175
µA
All Parts
0.5
VEN
ENABLE Input Voltage(6)
V
µA
V
VIH (MIN)
1.5
IEN
ENABLE Input Current
0V ≤ VEN ≤ 5V
1
5
VIN Rising
2
2.25
2.15
2.5
2.4
Under Voltage Lock Out
Threshold
UVLOTHRESHOLD
VIN Falling
1.9
Undervoltage Lock Out
Hysteresis
UVLOHYSTERESIS
VFAULT
0.1
V
V
Fault status Output
Voltage
IOL = 10mA
0.25
0.4
TJ Increasing
TJ Decreasing
145
135
Over-temperature
Threshold
OTTHRESHOLD
°C
February 2011
12
M9999-020311-D
Micrel, Inc.
MIC20xx Family
AC Electrical Characteristics
Symbol
Parameter
Condition
Min
Typ
Max
Units
RL = 10ꢀ, CLOAD = 1µF,
tRISE
Output Turn-on rise time
V
OUT = 10% to 90%
500
1000
1500
µs
CSLEW(7) = Open
Delay before asserting or
releasing FAULT/
Time from current limiting to FAULT/ state
change
20
32
49
MIC2003 – MIC2009
MIC2009A, MIC2005A
tD_FAULT
ms
Delay before asserting or
releasing FAULT/
Time from IOUT continuously exceeding primary
current limit condition to FAULT/ state change
77
77
128
128
192
192
MIC2013 – MIC2019
MIC2019A
Delay before current limiting
tD_LIMIT
ms
ms
MIC2013 – MIC2019
MIC2019A
Delay before resetting
Kickstart™ current limit delay,
tD_LIMIT
Out of current limit following a current limit
event.
tRESET
77
128
192
MIC2013 – MIC2019
MIC2019A
RL = 43ꢀ, CL = 120µF,
tON_DLY
Output Turn-on Delay
Output Turn-off Delay
V
EN = 50% to VOUT = 10%
1000
1500
700
µs
µs
*CSLEW = Open
RL = 43ꢀ, CL = 120µF,
VEN = 50% to VOUT = 90%
*CSLEW = Open
tOFF_DLY
ESD(8)
Symbol
Parameter
Condition
Min
Typ
Max
Units
VOUT and GND
±4
Electro Static Discharge
VESD_HB
kV
Voltage: Human Body Model
All other pins
±2
All pins
Electro Static Discharge
Voltage; Machine Model
VESD_MCHN
±200
V
Machine Model
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. Check the Ordering Information section to determine which parts are Active High or Active Low.
6.
V
V
IL(MAX) = Maximum positive voltage applied to the input which will be accepted by the device as a logic low.
IH(MAX) = Maximum positive voltage applied to the input which will be accepted by the device as a logic high.
7. Whenever CSLEW is present.
8. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
February 2011
13
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Timing Diagrams
tRISE
tFALL
90%
90%
10%
10%
Rise and Fall Times
ENABLE
50%
50%
tON_DLY
tOFF_DLY
90%
VOUT
10%
Switching Delay Times
February 2011
14
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Typical Characteristics
Supply Current Output
Disabled (MIC20XX)
Switch Leakage Current
(MIC20XX)
Supply Current Output Enabled
MIC20XX
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
100
80
85°C
60
25°C -40°C
40
85°C
20
5V
-40°C
25°C
0
2.5 3.0 3.5 4.0 4.5 5.0 5.5
VIN (V)
-40
-15
10
35
60
85
85
85
2.5 3.0 3.5 4.0 4.5 5.0 5.5
TEMPERATURE (°C)
V
(V)
IN
ILIMIT vs. Temperature
(MIC20XX - 1.2)
ILIMIT vs. Temperature
(MIC20XX - 0.5)
ILIMIT vs. Temperature
(MIC20XX - 0.8)
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1.5
2.00
1.90
1.80
1.70
1.60
1.50
1.40
1.30
1.20
1.10
1.00
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
5V
5V
5V
-40
-15
10
35
60
85
-40
-15
10
35
60
85
-40
-15
10
35
60
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
RDS(ON) vs. Temperature
(MIC20XX)
ILIMIT vs. Temperature
RDS(ON) vs. VIN
(MIC20XX)
(MIC20X9 - 0.9A)
RSET = 267Ohms
200
180
160
140
120
100
80
1200
1000
800
600
400
200
0
200
180
160
140
120
100
80
25°C
85°C
3.3V
2.5V
60
60
5.0V
-40°C
2.5
40
40
20
20
0
0
-40
-15
10
35
60
85
-40
-15
10
35
60
2
3
3.5
4
4.5
5
5.5
TEMPERATURE (°C)
TEMPERATURE (°C)
VIN (V)
VDROP vs. Temperature
VDROP vs. Temperature
RSET vs. ILIMIT
(MIC20X9)
242.62
(MIC20XX-1.2)
VIN = 5.0V
(MIC20XX-1.2)
VIN = 3.3V
160
140
120
100
80
160
140
120
100
80
1200
1000
800
600
400
200
0
RSET
=
0.9538
ILIMIT
85°C
85°C
25°C
25°C
60
60
-40°C
1
-40°C
40
40
20
20
0
0
0
0.2 0.4 0.6 0.8
IOUT (A)
1
1.2
0
0.2 0.4 0.6 0.8
1.2
0
0.2 0.4 0.6 0.8
ILIMIT (A)
1
1.2 1.4
IOUT (A)
February 2011
15
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Typical Characteristics (cont)
Supply Current Output Enabled
(MIC20XXA)
Supply Current Output
Disabled (MIC20XXA)
Switch Leakage Current
(MIC20XXA)
100
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
90
80
70
60
50
40
30
20
10
0
-40°C
85°C
25°C
85°C
-40°C
3.5
25°C
4.5
5V
2.5
3
3.5
4
4.5
5
5.5
2.5
3
4
5
5.5
-40
-15
10
35
60
85
VIN (V)
VIN (V)
TEMPERATURE (°C)
ILIMIT vs. Temperature
(MIC20X9A (0.8A))
RSET vs. ILIMIT
(MIC20X9A)
ILIMIT vs. Temperature
(MIC20X5A)
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1000
900
800
700
600
500
400
300
200
100
0
2500
2000
1500
1000
500
RSET = 267Ohms
212.23
RSET
=
5V
0.9587
ILIMIT
0
-40
-15
10
35
60
85
-40
-15
10
35
60
85
0
0.2
0.4
0.6
0.8
1
TEMPERATURE (°C)
TEMPERATURE (°C)
ILIMIT (A)
Flag Delay
vs. Temperature
RDS(ON) vs. Temperature
(MIC20XXA)
RDS(ON) vs. VIN
(MIC20XXA)
40
35
30
25
20
15
10
5
3.3V
2.5V
250
200
150
100
50
250
200
150
100
50
5.0V
2.5V
25°C
85°C
3.3V
5.0V
-40°C
0
0
0
2.5
3
3.5
4
4.5
5
5.5
-40
-15
10
35
60
85
-40
-15
10
35
60
85
VIN (V)
TEMPERATURE (°C)
TEMPERATURE (°C)
VDROP vs. Temperature
(MIC20XXA)
VDROP vs. Temperature
(MIC20XXA)
UVLO Threshold
vs. Temperature
160
140
120
100
80
160
140
120
100
80
2.3
2.25
2.2
VIN = 3.3V
VIN = 5.0V
V RISING
85°C
25°C
85°C
25°C
V FALLING
2.15
2.1
60
60
-40°C
-40°C
40
40
20
20
0
0
2.05
0
0.1 0.2 0.3 0.4 0.5 0.6
(A)
0
0.1 0.2 0.3 0.4 0.5 0.6
(A)
-50
0
50
100
150
I
I
OUT
TEMPERATURE (°C)
OUT
February 2011
16
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Functional Characteristics
February 2011
17
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Functional Characteristics (Continued)
February 2011
18
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Functional Characteristics (Continued)
February 2011
19
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Functional Diagram
Figure 2 MIC20XX Family Functional Diagram
February 2011
20
M9999-020311-D
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 bi-
directional 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.
Figure 3. Kickstart™ Operation
If discharging CLOAD is required by your application,
consider using MIC20X4 or MIC20X7; these MIC20XX
family members are equipped with a discharge FET to
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.
insure complete discharge of CLOAD
.
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.
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.
Kickstart™
2003 2004 2005X 2006 2007 2008 2009X
H. FAULT/ delay period followed by FAULT/ going
HIGH.
2013 2014
2015
2016
2017 2018 2019X
Only parts in bold 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
February 2011
21
M9999-020311-D
Micrel, Inc.
MIC20xx Family
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
2013
2004 2005X 2006
2014 2015
2016
2007
2017
2008 2009X
2018 2019X
Soft-start Control
Only parts in bold have VUVLO.
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.
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 is accomplished by controlling the power
MOSFET when the ENABLE pin enables the switch.
CSLEW
2003
2013
2004 2005X 2006
2014
2015 2016
2007
2017
2008 2009X
2018 2019X
Only parts in bold 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.
ENABLE
2003
2013
2004 2005X 2006
2014 2015 2016
2007
2017
2008 2009X
2018 2019X
Only parts in bold have ENABLE pin.
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 1.5 V.
ENABLE may be driven higher than VIN, but no higher
than 5.5V and not less than –0.3V.
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.
FAULT/
2003
2013
2004 2005X 2006
2014 2016
2015
2007
2017
2008 2009X
2018 2019X
Only parts in bold have FAULT/ pin.
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/ 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.
Because FAULT/ is an open-drain it must be pulled
HIGH with an external resistor and it may be wire-OR’d
February 2011
22
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Application Information
IOUT
0.1A
0.2A
0.3A
0.4A
0.5A
0.6A
0.7A
0.8A
0.9A
RSET
1928ꢀ
993ꢀ
673ꢀ
511ꢀ
413ꢀ
346ꢀ
299ꢀ
263ꢀ
235ꢀ
ILIMIT_MIN
0.063A
0.137A
0.216A
0.296A
0.379A
0.463A
0.548A
0.634A
0.722A
ILIMIT_MAX
0.136A
0.265A
0.391A
0.515A
0.637A
0.759A
0.880A
1.001A
1.121A
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:
CurrentLimitFactor(CLF)
ILIMIT
=
RSET
or
CurrentLimitFactor(CLF)
ILIMIT (A)
RSET
=
Table 2. MIC20x9A RSET Table
For example: Set ILIMIT = 1.25 A
Looking in the Electrical specifications we will find CLF
at ILIMIT = 1 A.
IOUT
0.2A
0.3A
0.4A
0.5A
0.6A
0.7A
0.8A
0.9A
1A
RSET
1125ꢀ
765ꢀ
582ꢀ
470ꢀ
395ꢀ
341ꢀ
300ꢀ
268ꢀ
243ꢀ
222ꢀ
204ꢀ
189ꢀ
176ꢀ
165ꢀ
ILIMIT_MIN
0.127A
0.202A
0.281A
0.361A
0.443A
0.526A
0.610A
0.695A
0.781A
0.868A
0.956A
1.044A
1.133A
1.222A
ILIMIT_MAX
0.267A
0.390A
0.510A
0.629A
0.746A
0.861A
0.976A
1.089A
1.202A
1.314A
1.426A
1.537A
1.647A
1.757A
Min
Typ
Max
Units
190
243
293
V
Table 1. CLF at ILIMIT = 1A
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:
243V
RSET (Ω) =
= 194.4Ω
1.25A
RSET = 196ꢀ
1.1A
1.2A
1.3A
1.4A
1.5A
(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
Table 3. MIC20x9 RSET Table
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.
CLF and the calculated value of RSET
.
190V
ILIMIT_MIN
ILIMIT_MAX
=
= 0.97A
= 1.5A
196Ω
293V
=
196ꢀ
Giving us a maximum ILIMIT variation over temperature of:
ILIMIT_MIN
ILIMIT_TYP
1.25A
ILIMIT_MAX
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.
0.97A (-22%)
1.5A (+20%)
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
February 2011
23
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Figure 5 this test is repeated but with VIN - VOUT
exceeding 1V.
Normalized Output Current
vs. Output Voltage (5V)
1.2
1.0
0.8
0.6
0.4
0.2
0
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.
0
1
2
3
4
5
6
OUTPUT VOLTAGE (V)
Figure 6. Normalized Output Current vs. Output Voltage
Normalized Output Current
vs. Output Voltage (2.5V)
1.2
1.0
0.8
0.6
0.4
0.2
0
Figure 4. IOUT in Current Limiting for VIN - VOUT < 1V
0
0.5 1.0 1.5 2.0 2.5 3.0
OUTPUT VOLTAGE (V)
Figure 7. Normalized Output Current vs. Output Voltage
CSLEW
2003
2013
2004 2005X 2006
2014
2015 2016
2007
2017
2008 2009X
2018 2019X
Only parts in bold 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 5. IOUT in Current Limiting for VIN - VOUT > 1V
This folding back of ILIMIT can be generalized by plotting
ILIMIT as a function of VOUT, as shown below in Figures 6
Figure 8 illustrates effect of CSLEW on turn-on delay and
output rise time.
and 7. The slope of VOUT between IOUT = 0V and IOUT
=
ILIMIT (where ILIMIT = 1A) is determined by RON of the
switch and ILIMIT
February 2011
.
24
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Typical Turn-on Times
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.
vs. External CSLEW Capacitance
14
0.014
TON
12
0.012
TDELAY
10
0.01
8
0.008
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.
6
0.006
4
TRISE
0.004
2
0.002
0
0
0
0.5
1
1.5
2
4
3
3.5
2.5
0 0 0
4.5
0
0
0
0
0
0
0
CSLEW (nF)
Figure 8. CSLEW vs. Turn-On, Delay and Rise TImes
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.
Variable Under Voltage Lock Out (VUVLO)
2003
2013
2004 2005X 2006
2014 2015
2016
2007
2017
2008 2009X
2018 2019X
Only parts in bold have VUVLO pin and functionality.
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
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.
Figure 9. VUVLO Operation
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.
IIN_LOAD
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. During 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.
Input
Supply
VIN
VOUT
MIC20X6
VUVLO
R1
R2
+
+
Figure 10. VUVLO Application Circuit
Calculating VUVLO Resistor Divider Values
The VUVLO feature is designed to keep the internal
switch off until the voltage on the VUVLO pin is greater
than 0.25V. A resistor divider network connected to the
VUVLO and VIN pins is used to set the input trip voltage
VTRIP, see Figure 10. The value of R2 is chosen to
minimize the load on the input supply IDIV and the value
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
of R1 sets the trip voltage VTRIP
.
February 2011
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M9999-020311-D
Micrel, Inc.
MIC20xx Family
The value of R2 is calculated using:
limit (ILIMIT_2nd) to the load for 128ms and then normal
(primary) current limiting goes into action.
VVUVLO
R2 =
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.
IDIV
The vale of R1 is calculated using:
⎛
⎞
VTRIP
⎜
⎜
⎟
− 1
R1 = R2×
⎟
VVUVLO
⎝
⎠
Where for both equations:
VVUVLO = 0.25V
When working with large value resistors, a small amount
of leakage current from the VUVLO terminal can cause
voltage offsets that degrade system accuracy.
Therefore, the maximum recommended resistor value
for R2 is 100kꢀ.
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.
Using the divider loading current IDIV of 100uA, the value
of R2 can be estimated by:
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
0.25V
R2 =
= 2.5kΩ
100µA
Now the value of R1 can be calculated by:
ILIMIT_2nd
.
4.75V
0.25V
⎛
⎜
⎞
R1= 2.5kΩ ×
−1 = 45k
⎟
⎝
⎠
Where:
VTRIP = 4.75V (for a 5V supply)
VUVLO = 0.25V
V
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 11. Kickstart™
Automatic Load Discharge
Kickstart™
2003
2013
2004 2005X 2006
2014
2015 2016
2007
2017
2008 2009X
2018 2019X
2003
2004 2005X 2006
2014 2015 2016
2007
2008 2009X
2013
2017
2018 2019X
Only parts in bold have automatic load discharge.
Only parts in bold have Kickstart™.
(Not available in 5-pin SOT-23 packages).
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™.
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
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
February 2011
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M9999-020311-D
Micrel, Inc.
MIC20xx Family
MOSFET. The total resistance of the MOSFET and
internal resistances is typically 126ꢀ.
assuming a constant case temperature of 85°C. The
plots also assume a worst case RON of 140mꢀ 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 switches
for any design intending to supply continuous currents of
1A or more.
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.
Die Temperature vs.
Output Current (T
160
=85°C)
CASE
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.
140
SOT-23
120
100
80
60
40
20
0
MLF
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:
2
0.2 0.4 0.6 0.81.0 1.21.4 1.6 1.82.0
OUTPUT CURRENT (A)
Figure 12. Die Temperature vs. IOUT
PD = RDS(ON) × (IOUT
)
To relate this to junction temperature, the following
equation can be used:
TJ = PD ×Rθ(J−A) + TA
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
no significant I2R 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 12 die temperature is plotted against IOUT
February 2011
27
M9999-020311-D
Micrel, Inc.
MIC20xx Family
Package Information
5-Pin SOT-23 (M5)
6-Pin SOT-23 (M6)
February 2011
28
M9999-020311-D
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
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right.
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
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