MIC20XX_1108 [MICREL]
Fixed and Adjustable Current Limiting Power Distribution Switches; 固定和可调电流限制配电开关
| 型号： | MIC20XX_1108 |
| 厂家： | 
MICREL SEMICONDUCTOR |
| 描述： | Fixed and Adjustable Current Limiting Power Distribution Switches |
| 文件： | 总30页 (文件大小：1314K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
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 and Pin Configuration
drawings)
• 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)
• Undervoltage 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
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.
• Digital televisions (DTV)
• Set top boxes
• PDAs
• 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
M9999-080211-D
August 2011
Micrel, Inc.
MIC20xx Family
Ordering Information
MIC2003/2013
Part Number(1)
Marking(2)
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
FD05
FD08
FD12
5-Pin SOT-23
0.8A
1.2A
No
0.5A
D05
D08
6-Pin 2mm x 2mm MLF®
5-Pin SOT-23
0.8A
1.2A
D12
FL05
0.5A
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)
FE05
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
5-Pin SOT-23
FE08
0.8A
FE12
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.
August 2011
2
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Ordering Information (Continued)
MIC2005
Part Number(1)
Marking(2)
FF05
Current Limit
0.5A
Enable
Kickstart™ Package
MIC2005-0.5YM6
MIC2005-0.8YM6
MIC2005-1.2YM6
MIC2005-0.5YML
MIC2005-0.8YML
MIC2005-1.2YML
Active High
Active High
Active High
Active High
Active High
Active High
6-Pin SOT-23
FF08
0.8A
FF12
1.2A
No
0.5A
F05
F08
F12
6-Pin 2mm x 2mm MLF®
0.8A
1.2A
MIC2005L
Part Number(1)
MIC2005-0.5LYM5
MIC2005-0.8LYM5
MIC2005-1.2LYM5
Marking(2)
5LFF
Current Limit
0.5A
Enable
Kickstart™ Package
Active Low
Active Low
Active Low
No
5-Pin SOT-23
8LFF
0.8A
4LFF
1.2A
MIC2005A
Part Number(1)
MIC2005A-1YM5
MIC2005A-2YM5
MIC2005A-1YM6
MIC2005A-2YM6
Marking(2)
FA51
Current Limit
0.5A
Enable
Kickstart™ Package
Active High
Active Low
Active High
Active Low
5-Pin SOT-23
FA52
0.5A
No
FA53
0.5A
6-Pin SOT-23
FA54
0.5A
MIC2015
Part Number(1)
MIC2015-0.5YM6
MIC2015-0.8YM6
MIC2015-1.2YM6
MIC2015-0.5YML
MIC2015-0.8YML
Marking(2)
FN05
Current Limit
0.5A
Enable
Kickstart™ Package
Active High
Active High
Active High
Active High
Active High
Active High
6-Pin SOT-23
FN08
0.8A
FN12
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.
August 2011
3
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Ordering Information (Continued)
MIC2006/2016
Part Number(1)
Marking(2)
FG05
Current Limit
0.5A
Kickstart™ Package
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
6-Pin SOT-23
FG08
0.8A
FG12
1.2A
No
0.5A
G05
G08
6-Pin 2mm x 2mm MLF®
6-Pin SOT-23
0.8A
1.2A
G12
FP05
FP08
FP12
0.5A
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
Marking(2)
Current Limit
Kickstart™ Package
FKAA
6-Pin SOT-23
6-Pin 2mm x 2mm MLF®
No
MIC2009YML
MIC2019YM6
KAA
0.2A – 2.0A
FSAA
6-Pin SOT-23
Yes
MIC2019YML
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.
August 2011
4
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Ordering Information (Continued)
MIC2009A/2019A
Part Number(1)
MIC2009A-1YM6
MIC2009A-2YM6
MIC2019A-1YM6
Marking(2) Current Limit Kickstart™ Enable
Package
FK1
FK2
FS1
FS2
Active High
Active Low
Active High
Active Low
No
0.1 A – 0.9 A
6-pin SOT-23
Yes
MIC2019A-2YM6
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.
MIC20XX Family Member Functionality
Part Number
Pin Function
Normal
Limiting
ENABLE
High
ENABLE
Low
Load
Discharge
Kickstart™(1)
ILIMIT
ILIMIT
CSLEW FAULT/
VUVLO(5)
2003
2013
2014
2015
–
─
–
–
─
–
─
–
–
─
─
─
─
─
▲
─
─
─
─
─
─
▲
─
─
─
─
─
▲
─
─
─
─
2004
2005
▲
▲
─
─
─
─
▲
─
▲
▲
▲
▲
─
Fixed (2)
(1)
2005L
2005A-1
2005A-2
2006
─
─
▲
─
(1)
(6)
─
─
▲
─
─
─
(1)
(6)
─
─
▲
─
2016
2017
─
▲
▲
▲
▲
▲
─
▲
2007
▲
▲
▲
▲
▲
─
▲
▲
─
─
2008
2018
─
─
Adj.(3)
2009
2019
─
▲
▲
▲
2009A-1
2019A-1
2019A-2
─
─
2009A-2
▲
─
Notes:
1. Kickstart™ provides an alternate start-up behavior; however, pin-outs are identical.
2. Kickstart™ not available.
3. Fixed = Factory-programmed current limit.
4. Adj. = User adjustable current limit.
5. VUVLO = Variable UVLO (Previously called DML).
6. CSLEW not available in 5-pin package.
August 2011
5
M9999-080211-D
Micrel, Inc.
MIC20xx Family
MIC20XX Family Member Pin Configuration Table, SOT Packages
Part Number
Pin Number
ILIMIT
Normal
Limiting
Kickstart™
1
2
3
4
5
6
2003
2013
2014
2015
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
VIN
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
NC
EN
EN
EN
EN
EN
EN
EN
EN
EN
EN
─
NC
VOUT
VOUT
CSLEW
VOUT
2004
2005
─
NC
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
CSLEW
CSLEW
ILIMIT
VOUT
VOUT
VOUT
VOUT
VOUT
2007
2008
ILIMIT
Adj.(3)
2009
FAULT/
FAULT/
2009A
ILIMIT
Notes:
1. Kickstart™ not available.
2. Fixed = Factory-programmed current limit.
3. LIMIT = User adjustable current limit.
4. VUVLO = Variable UVLO (Previously called DLM).
I
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.
August 2011
6
M9999-080211-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)
August 2011
7
M9999-080211-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)
August 2011
8
M9999-080211-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
VIN
Input
Supply input. This pin provides power to both the output switch and the switch’s internal control circuitry.
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
Input
ILIMIT
EP
Set current limit threshold via a resistor connected from ILIMIT to GND.
Thermal On MLF packages connect EP to GND.
Signal Descriptions
Signal Name
VIN
Type
Input
─
Description
Electrical signal input voltage present at the VIN pin.
Ground.
GND
VEN
Input
Output
Electrical signal input voltage present at the ENABLE pin.
Electrical signal output voltage present at the FAULT/ pin.
VFAULT/
CSLEW
VOUT
Component Capacitance value connected to the CSLEW pin.
Output
Electrical signal output voltage present at the VOUT pin.
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 Capacitance value connected in parallel with the load. Load capacitance.
Output
Electrical signal output current present at the VOUT pin.
Switch’s current limit. Fixed at factory or user adjustable.
ILIMIT
Internal
August 2011
9
M9999-080211-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) .........................................230°C /W
2mm × 2mm MLF® (θJA) ................................90°C /W
2mm × 2mm MLF® (θJC)................................45°C /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
MIC2005A, MIC2009A, MIC2019A
Switch = ON
Active Low Enable, VEN = 0V
Active High Enable, VEN = 1.5V
80
8
300
IIN
Supply Current(5)
µA
Switch = OFF
Active Low Enable, VEN = 1.5V
15
5
Switch = OFF
Active High Enable, VEN = 0V
1
170
220
RDS(ON)
Power Switch Resistance
Fixed Current Limit
VIN = 5V, IOUT = 100mA
VOUT = 0.8 × VIN
mΩ
275
MIC2005A
ILIMIT
0.5
0.7
0.9
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
V
A
I
OUT = 0.1A, VOUT = 0.8 × VIN
MIC2019A
ILIMIT_2nd
Secondary Current Limit
VIN = 2.5V, VOUT = 0V
1
2
3
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.
August 2011
10
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Electrical Characteristics(4) (Continued)
VIN = 5V, TA = 25°C unless otherwise specified. Bold indicates –40°C to +85°C limits; CIN = 1µF.
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
IIN
Supply Current(5)
µA
Switch = OFF
15
5
Active Low Enable, VEN = 1.5V
Switch = OFF
Active High Enable, VEN = 0V
1
70
100
RDS(ON)
Power Switch Resistance
VIN = 5V, IOUT = 100mA
mΩ
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
0.8
1.2
0.7
1.1
1.6
0.9
1.5
2.1
−0.5, VOUT = 0.8 × VIN
−0.8, VOUT = 0.8 × VIN
−1.2, VOUT = 0.8 × VIN
ILIMIT
Fixed Current Limit
A
A
MIC2005-0.5
ILIMIT
Fixed Current Limit
0.5
0.7
0.9
VOUT = 0.8 × VIN
MIC2007, MIC2008, MIC2009, MIC2017, MIC2018, MIC2019
IOUT = 2.0A, VOUT = 0.8 × VIN
210
190
168
144
250
243
235
225
286
293
298
299
IOUT = 1.0A, VOUT = 0.8 × VIN
IOUT = 0.5A, VOUT = 0.8 × VIN
IOUT = 0.2A, VOUT = 0.8 × VIN
Variable Current Limit
Factors
CLF
V
MIC2013, MIC2014, MIC2015, MIC2016, MIC2017, MIC2018, MIC2019
ILIMIT_2nd
Secondary Current Limit
Variable UVLO Threshold
Load Discharge Resistance
VIN = 2.5V, VOUT = 0V
2.2
225
70
4
6
A
mV
Ω
MIC2006, MIC2016
VUVLO_TH
250
275
200
MIC20x4, MIC20x7
RDSCHG
VIN = 5V, ISINK = 5mA
126
MIC20X5, MIC20X6, MIC20X7, MIC20X8
ICSLEW
CSLEW Input Current
0.175
µA
0V ≤ VOUT ≤ 0.8VIN
August 2011
11
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Electrical Characteristics(4) (Continued)
VIN = 5V, TA = 25°C unless otherwise specified. Bold indicates –40°C to +85°C limits; CIN = 1µF.
Symbol
Parameter
Condition
Min.
Typ.
Max.
0.5
Units
All Parts
VIL (MAX)
VEN
ENABLE Input Voltage(6)
ENABLE Input Current
V
µA
V
VIH (MIN)
1.5
IEN
1
5
0V ≤ VEN ≤ 5V
VIN Rising
2
2.25
2.15
2.5
2.4
Undervoltage 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
145
135
0.4
TJ Increasing
TJ Decreasing
Over-Temperature
Threshold
OTTHRESHOLD
°C
Note:
6. VIL(MAX) = Maximum positive voltage applied to the input which will be accepted by the device as a logic low.
VIH(MAX) = Maximum positive voltage applied to the input which will be accepted by the device as a logic high.
August 2011
12
M9999-080211-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
77
128
128
192
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
128
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%
tOFF_DLY
*CSLEW = Open
ESD(8)
Symbol
Parameter
Condition
Min.
Typ.
Max.
Units
VOUT and GND
±4
Electro Static Discharge Voltage:
Human Body Model
VESD_HB
kV
All other pins
±2
All pins
Electro Static Discharge Voltage;
Machine Model
VESD_MCHN
±200
V
Machine Model
Notes:
7. Whenever CSLEW is present.
8. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
August 2011
13
M9999-080211-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
August 2011
14
M9999-080211-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)
August 2011
15
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Typical Characteristics (Continued)
Supply Current Output Enabled
(MIC20XXA)
Supply Current Output
Disabled (MIC20XXA)
Switch Leakage Current
(MIC20XXA)
100
90
80
70
60
50
40
30
20
10
0
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
-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
August 2011
16
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Functional Characteristics
August 2011
17
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Functional Characteristics (Continued)
August 2011
18
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Functional Characteristics (Continued)
August 2011
19
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Functional Diagram
Figure 2. MIC20XX Family Functional Diagram
August 2011
20
M9999-080211-D
Micrel, Inc.
MIC20xx Family
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
of Kickstart™ operation is shown in Figure 3.
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.
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
.
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.
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).
Kickstart™
2003 2004 2005X 2006 2007 2008 2009X
2013 2014
2015
2016 2017 2018 2019X
Only parts in bold have Kickstart™.
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.
(Not available in 5-pin SOT-23 packages)
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.
Undervoltage Lock-Out
Undervoltage 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.
August 2011
21
M9999-080211-D
Micrel, Inc.
MIC20xx Family
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.
Variable Undervoltage Lock Out (VUVLO)
2003
2013
2004 2005X 2006
2014 2015
2016
2007
2017
2008 2009X
2018 2019X
Only parts in bold 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.
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.
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.
ENABLE
2003
2013
2004 2005X 2006
2014 2015 2016
2007
2017
2008 2009X
2018 2019X
CSLEW
Only parts in bold have ENABLE pin.
2003
2013
2004 2005X 2006
2014
2015 2016
2007
2017
2008 2009X
2018 2019X
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.
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 may be driven higher than VIN, but no higher
than 5.5V and not less than –0.3V.
FAULT/
Thermal Shutdown
2003
2013
2004 2005X 2006
2014 2016
2015
2007
2017
2008 2009X
2018 2019X
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.
Only parts in bold 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.
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/ 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.
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.
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
August 2011
22
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Giving us a maximum ILIMIT variation over temperature
of:
Application Information
Setting ILIMIT
The MIC2009/2019’s current limit is user programmable
and controlled by a resistor connected between the
ILIMIT pin and GND. The value of this resistor is
determined by the following equation:
ILIMIT_MIN
ILIMIT_TYP
1.25A
ILIMIT_MAX
0.97A (-22%)
1.5A (+20%)
IOUT
RSET
ILIMIT_MIN
ILIMIT_MAX
0.136A
0.265A
0.391A
0.515A
0.637A
0.759A
0.880A
1.001A
1.121A
0.1A
0.2A
0.3A
0.4A
0.5A
0.6A
0.7A
0.8A
0.9A
1928ꢀ
993ꢀ
673ꢀ
511ꢀ
413ꢀ
346ꢀ
299ꢀ
263ꢀ
235ꢀ
0.063A
0.137A
0.216A
0.296A
0.379A
0.463A
0.548A
0.634A
0.722A
CurrentLimitFactor(CLF)
ILIMIT
=
=
RSET
or
CurrentLimitFactor(CLF)
ILIMIT (A)
RSET
For example: Set ILIMIT = 1.25A
Looking in the Electrical specifications we will find CLF
at ILIMIT = 1A.
Min
Typ
Max
Units
Table 2. MIC20x9A RSET Table
190
243
293
V
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
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
R
SET = 196ꢀ
(the closest standard 1% value)
1.1A
1.2A
1.3A
1.4A
1.5A
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
Table 3. MIC20x9 RSET Table
values of CLF and the calculated value of RSET
.
190V
ILIMIT_MIN
=
= 0.97A
= 1.5A
196Ω
293V
ILIMIT_MAX
=
196ꢀ
August 2011
23
M9999-080211-D
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.
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
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 ꢀ’s law by the
load and the limiting current.
and 7. The slope of VOUT between IOUT = 0V and IOUT
ILIMIT (where ILIMIT = 1A) is determined by RON of the
switch and ILIMIT
=
.
Normalized Output Current
vs. Output Voltage (5V)
1.2
1.0
0.8
0.6
0.4
0.2
0
0
1
2
3
4
5
6
OUTPUT VOLTAGE (V)
Figure 6. Normalized Output Current vs. Output Voltage
Figure 4. IOUT in Current Limiting for VIN - VOUT < 1V
August 2011
24
M9999-080211-D
Micrel, Inc.
MIC20xx Family
Normalized Output Current
vs. Output Voltage (2.5V)
CSLEW’s Effect on ILIMIT
1.2
1.0
0.8
0.6
0.4
0.2
0
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.
0
0.5 1.0 1.5 2.0 2.5 3.0
OUTPUT VOLTAGE (V)
Variable Undervoltage Lock Out (VUVLO)
2003
2013
2004 2005X 2006
2014 2015
2016
2007
2017
2008 2009X
2018 2019X
Figure 7. Normalized Output Current vs. Output Voltage
CSLEW
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.
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.
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.
Figure 8 illustrates effect of CSLEW on turn-on delay and
output rise time.
Typical Turn-on Times
vs. External CSLEW Capacitance
14
0.014
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.
TON
12
0.012
TDELAY
10
0.01
8
0.008
6
0.006
4
TRISE
0.004
2
0.002
0
0
0
4
3
3.5
0 0 0
4.5
0
0.5 1 1.5 2
2.5
0
0
0
0
0
0
CSLEW (nF)
Figure 8. CSLEW vs. Turn-On, Delay and Rise Times
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MIC20xx Family
To prevent false triggering of the VUVLO feature, the
Calculating VUVLO Resistor Divider Values
MIC20X6 includes
a
delay timer to blank out
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
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.
the value of R1 sets the trip voltage VTRIP
.
The value of R2 is calculated using:
VVUVLO
R2 =
IDIV
The vale of R1 is calculated using:
⎛
⎞
VTRIP
⎜
⎜
⎟
− 1
R1 = R2×
⎟
VVUVLO
⎝
⎠
Where for both equations:
VUVLO = 0.25V
V
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.
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.
Using the divider loading current IDIV of 100µA, the
value of R2 can be estimated by:
0.25V
R2 =
= 2.5kΩ
IIN_LOAD
100µA
Input
Supply
VIN
VOUT
MIC20X6
VUVLO
Now the value of R1 can be calculated by:
R1
R2
+
+
4.75V
0.25V
⎛
⎜
⎞
R1= 2.5kΩ×
−1 = 45k
⎟
⎝
⎠
Figure 10. VUVLO Application Circuit
where:
V
TRIP = 4.75V (for a 5V supply)
VUVLO = 0.25V
V
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MIC20xx Family
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.
Kickstart™
2003
2004 2005X 2006
2014 2015 2016
2007
2008 2009X
2013
2017
2018 2019X
Only parts in bold have Kickstart™.
(Not available in 5-pin SOT-23 packages).
Figure 11. Kickstart™
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.
2003
2013
2004 2005X 2006
2014
2015 2016
2007
2017
2008 2009X
2018 2019X
Only parts in bold have automatic load discharge.
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.
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™.
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
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 126ꢀ.
I
OUT to its programmed limit for as long as the excessive
Supply Filtering
load persists.
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.
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
.
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.
August 2011
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M9999-080211-D
Micrel, Inc.
MIC20xx Family
Power Dissipation
In Figure 12, die temperature is plotted against IOUT
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.
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
PD = RDS(ON) × (IOUT
)
To relate this to junction temperature, the following
equation can be used:
Die Temperature vs.
Output Current (T
160
=85°C)
CASE
TJ = PD ×Rθ
+ TA
(J−A)
140
SOT-23
120
100
80
60
40
20
0
where:
MLF
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.
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
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M9999-080211-D
Micrel, Inc.
MIC20xx Family
Package Information
5-Pin SOT-23 (M5)
6-Pin SOT-23 (M6)
August 2011
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Micrel, Inc.
MIC20xx Family
Package Information (Continued)
6 Pin 2mm x 2mm MLF® (ML)
Section 1.01 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
indemnify Micrel for any damages resulting from such use or sale.
© 2009 Micrel, Incorporated.
August 2011
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M9999-080211-D
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