MIC5156/5157/5158
Micrel, Inc.
MIC5156/5157/5158
Super LDO™ Regulator Controller
General Description
The MIC5156, MIC5157, and MIC5158 Super Low-Dropout
(LDO) Regulator Controllers are single IC solutions for high-
current low-dropout linear voltage regulation. Super LDO™
Regulators have the advantages of an external N-channel
power MOSFET as the linear pass element.
The MIC5156/7/8 family features a dropout voltage as low
as the R
DS(ON)
of the external power MOSFET multiplied by
the output current. The output current can be as high as the
largest MOSFETs can provide.
The MIC5156/7/8 family operates from 3V to 36V. The
MIC5156 requires an external gate drive supply to provide
the higher voltage needed to drive the gate of the external
MOSFET. The MIC5157 and MIC5158 each have an inter-
nal charge pump tripler to produce the gate drive voltage.
The tripler is capable of providing enough voltage to drive a
logic-level MOSFET to 3.3V output from a 3.5V supply and
is clamped to 17.5V above the supply voltage. The tripler
requires three external capacitors.
The regulator output is constant-current limited when the
controller detects 35mV across an optional external sense
resistor. An active-low open-collector flag indicates a low
voltage of 8% or more below nominal output. A shutdown
(low) signal to the TTL-compatible enable control reduces
controller supply current to less than 1µA while forcing the
output voltage to ground.
The MIC5156-3.3 and MIC5156-5.0 controllers have inter-
nally fixed output voltages. The MIC5156 [adjustable] output
is configured using two external resistors. The MIC5157 is a
fixed output controller which is externally configured to select
either 3.3V, 5.0V, or 12V. The MIC5158 can be configured
as a fixed 5V controller or programmed to any voltage from
1.3V to 36V using two external resistors.
The MIC5156 is available in an 8-pin DIP or SOIC. The
MIC5157 and MIC5158 are available in a 14-pin DIP or SOIC
which operate from –40°C to +85°C.
Features
•
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•
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4.5mA typical operating current
<1µA typical standby current
Low external parts count
Optional current limit (35mV typical threshold)
1% initial output voltage tolerance in most configurations
2% output voltage tolerance over temperature
Fixed output voltages of 3.3V, 5.0V (MIC5156)
Fixed output voltages of 3.3V, 5.0V, 12V (MIC5157)
Programmable (1.3 to 36V) with 2 resistors (MIC5156/8)
Internal charge pump voltage tripler (MIC5157/8)
Enable pin to activate or shutdown the regulator
Internal gate-to-source protective clamp
All versions available in DIP and SOIC
Ultrahigh current ultralow dropout voltage regulator
Constant high-current source
Low parts count 5.0V to 3.3V computer supply
Low noise/low-dropout SMPS post regulator
High-current, current-limited switch
Applications
Typical Applications
+12V
0.1µF
Enable
Shutdown
0.1µF
7
C
1.0µF
4
V
P
3
G
2
F
1
E
6
C
5
V
C
4
G
F
3
3
S
2
1
5
MIC5156-3.3
C –
V
D
G
D
MIC5157
V
D
G
C
D
S
5
V
IN
5V
3mΩ
47µF
6
7
8
V
OU T
3.3V, 10A
8
9
10
11 12 13
0.1µF
R
S
R
S
= 0.035V /I
LIMIT
SMP60N03-10L
C
L
*
47µF
*Improves transient
response to load changes
V
IN
(3.61Vmin.)
3mΩ
R
S
Enable
Shutdown
E
14
C
L
*
47µF
R
S
= 0.035V /I
LIMIT
*Improves transient
IRLZ44 (Logic Level MOSFET) response to load changes
47µF
V
OU T
3.3V, 10A
10A 5V to 3.3V Desktop Computer Regulator
Super LDO
is a trademark of Micrel, Inc.
10A Low-Dropout Voltage Regulator
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
August 2005
1
MIC5156/5157/5158
MIC5156/5157/5158
Micrel, Inc.
Part Number
Pb-Free
MIC5156-3.3YN
MIC5156-5.0YN
MIC5156YN
MIC5156-3.3YM
MIC5156-5.0YM
MIC5156YM
Voltage
3.3V
5.0V
Adj
3.3V
5.0V
Adj
Temperature
Range
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
Package
8-pin DIP
8-pin DIP
8-pin DIP
8-pin SOIC
8-pin SOIC
8-pin SOIC
Ordering Information MIC5156
Standard
MIC5156-3.3BN
MIC5156-5.0BN
MIC5156BN
MIC5156-3.3BM
MIC5156-5.0BM
MIC5156BM
Ordering Information MIC5157
Standard
MIC5157BN
MIC5157BM
Part Number
Pb-Free
MIC5157YN
MIC5157YM
Voltage
Selectable
Selectable
Temperature
Range
–40°C to +85°C
–40°C to +85°C
Package
14-pin DIP
14-pin SOIC
Ordering Information MIC5158
Standard
MIC5158BN
MIC5158BM
Part Number
Pb-Free
MIC5158YN
MIC5158YM
Voltage
5.0V/Adj
5.0V/Adj
Temperature
Range
–40°C to +85°C
–40°C to +85°C
Package
14-pin DIP
14-pin SOIC
Pin Configuration
MIC5156-x.x
EN 1
FLAG 2
GND 3
V
P
4
8 S (Source)
7 D (Drain)
6 G (Gate)
5 V
D D
MIC5156
EN 1
FLAG 2
GND 3
V
P
4
8
EA
7 D (Drain)
6 G (Gate)
5 V
D D
MIC5157
5V 1
3.3V 2
FLAG 3
GND 4
14 E N
13 S (Source)
12 D (Drain)
11 G (Gate)
EA 1
5V FB 2
FLAG 3
GND 4
MIC5158
14 E N
13 S (Source)
12 D (Drain)
11 G (Gate)
V
C P
5
C2– 6
C2+ 7
10 V
D D
9 C1–
8 C1+
V
C P
5
C2– 6
C2+ 7
10 V
D D
9 C1–
8 C1+
MIC5156/5157/5158
2
August 2005
MIC5156/5157/5158
Micrel, Inc.
Pin Description MIC5156
Pin Number
1
2
3
4
5
Pin Name
EN
FLAG
GND
V
P
V
DD
G
D
Pin Function
Enable (Input): TTL high enables regulator; TTL low shuts down regulator.
Output Flag (Output): Open collector output is active (low) when V
OUT
is more
than 8% below nominal output. Circuit has 3% hysteresis.
Circuit ground.
N-channel Gate Drive Supply Voltage: User supplied voltage for driving the
gate of the external MOSFET.
Supply Voltage (Input): Supply voltage connection. Connect sense resis-
tor (R
S
) to V
DD
if current limiting used. Connect supply bypass capacitor to
ground near device.
Gate (Output): Drives the gate of the external MOSFET.
Drain and Current Limit (Input): Connect to external MOSFET drain and ex-
ternal sense resistor (current limit), or connect to V
DD
and external MOSFET
drain (no current limit).
Source (Input): Top of internal resistive divider chain. Connect directly to the
load for best load regulation.
Error Amplifier (Input): Connect to external resistive divider.
6
7
8 (3.3V, 5V)
8 (adjustable)
S
EA
Pin Description MIC5157, MIC5158
Pin Number
1 (MIC5157)
1 (MIC5158)
2 (MIC5157)
2 (MIC5158)
3
4
5
6
7
8
9
10
Pin Name
5V
EA
3.3V
5V FB
FLAG
GND
C2–
C2+
C1+
C1–
V
DD
G
D
V
CP
Pin Function
5V Configuration (Input): Connect to S (source) pin for 5V output.
Error Amplifier (Input): Connect to external resistive divider to obtain adjust-
able output.
3.3V Configuration (Input): Connect to S (source) pin for 3.3V output.
5V Feedback (Input): Connect to EA for fixed 5V output.
Output Voltage Flag (Output): Open collector is active (low) when V
OUT
is 8%
or more below its nominal value.
Circuit ground.
Voltage Tripler Output [Filter Capacitor]. Connect a 1 to 10µF capacitor to ground.
Charge Pump Capacitor 2: Second stage of internal voltage tripler. Connect a
0.1µF capacitor from C2+ to C2–.
Charge Pump Capacitor 2: See C2– pin 6.
Charge Pump Capacitor 1: First stage of internal voltage tripler. Connect a
0.1µF capacitor from C1+ to C1–.
Charge Pump Capacitor 1: See C1+ pin 8.
Supply Voltage (Input): Supply voltage connection. Connect sense resis-
tor (R
S
) to V
DD
if current limiting used. Connect supply bypass capacitor to
ground near device.
Gate (Output): Connect to External MOSFET gate.
Drain and Current Limit (Input): Connect to external MOSFET drain and ex-
ternal sense resistor (current limit), or connect to V
DD
and external MOSFET
drain (no current limit).
Source and 3.3V/5V Configuration: Top of internal resistor chain. Connect to
source of external MOSFET for 3.3V, 5V, and 12V operation. Also see 3.3V
and 5V pin descriptions.
Source (Input): Top of internal resistor chain. Connect to top of external resis-
tive divider and source of external MOSFET.
Enable (Input): TTL high enables regulator; TTL low shuts down regulator.
11
12
13 (MIC5157)
S
13 (MIC5158)
14
S
EN
August 2005
3
MIC5156/5157/5158
MIC5156/5157/5158
Micrel, Inc.
Absolute Maximum Ratings
(Note 1)
Supply Input (V
DD
)....................................................... +38V
Enable Input (V
EN
) ..........................................–0.3V to 36V
Gate Output (V
G
) MIC5156 ......................................... +55V
Charge Pump Node (V
CP
) MIC5157/8 ........................ +55V
Source Connection (V
S
) ................................... 1.3 to +36V
Flag (V
FLAG
) .................................................... –0.3 to +40V
Storage Temperature (T
S
) ........................ –65°C to +150°C
Lead Temperature (soldering 10 sec.) ....................... 300°C
Operating Ratings
(Note 2)
Ambient Temperature Range (T
A
)
MIC515xBM/BN ...................................... –40°C to +85°C
Junction Temperature (T
J
) ....................................... +150°C
Thermal Resistance (θ
JA
)
Package
MIC5156
MIC5157/8
DIP ................................ 100°C/W ..................... 90°C/W
SOIC ............................. 160°C/W ................... 120°C/W
Electrical Characteristics
(Note 5)
V
DD
= 5V, V
EN
= 5V; T
A
= 25°C; unless noted.
Symbol
Parameter
V
DD
Supply Voltage
Supply Current MIC5156
Supply Current MIC5157/8
Enable Input Threshold
Enable Input Bias Current
Max. Charge Pump Voltage
Charge Pump Frequency
Maximum Gate Drive Voltage
(MIC5157/8)
Operating, V
EN
= 5V
Shutdown, V
EN
= 0V
Operating, V
EN
= 5V
Shutdown, V
EN
= 0V
Condition
Min
3
2.7
0.1
4.5
0.1
2.4
1.3
1.3
20
17.5
160
5
9
24
28
3.267
4.950
3.250
4.950
11.70
4.925
1.222
14
7.0
11.3
28
1.0
35
3.3
5.0
3.3
5.0
12
5.0
1.235
2
16.6
92
3
0.09
0.2
42
3.333
5.050
3.350
5.050
12.30
5.075
1.248
7
20
9
15
30
Typ
Max
36
10
5
10
5
0.8
25
18.5
Units
V
mA
µA
mA
µA
V
V
µA
V
kHz
V
V
V
V
mV
V
V
V
V
V
V
V
mV
V
%
%
V
I
DD(ON)
I
DD(OFF)
I
DD(ON)
I
DD(OFF)
V
IH
V
IL
High
Low
EN I
B
V
CP
f
CP
V
CP
– V
DD
, V
DD
> 10V
V
SOURCE
= 0V
V
DD
= 3.5V
V
DD
= 5V
V
DD
= 12V
V
EN
= 2.4V
V
OUT MAX
V
OUT MIN
V
LIM
V
S
Minimum Gate Drive Voltage
Current Limit Threshold
Source Voltage
V
SOURCE
> V
OUT(NOM)
V
DD
– V
D
@ I
LIM
Short G (gate) to (S) source,
Note 4
MIC5156-3.3
MIC5156-5.0
MIC5157, 3.3V pin to S pin (3.3V config.)
MIC5157, 5V pin to S pin (5V config.)
MIC5157, V
DD
= 7V, (12V config.)
MIC5158, 5V FB pin to EA pin (5V config.)
V
BG
V
LR
V
FT
V
GS MAX
V
FH
Bandgap Reference Voltage
Output Voltage Line Regulation
Gate to Source Clamp
Flag Comparator Threshold
Flag Comparator Hysteresis
Flag Comparator Sat. Voltage
MIC5156 [adjustable] and MIC5158
5V < V
DD
< 15V, V
OUT
= 3.3V
% of nominal V
SOURCE
I
FLAG
= 1mA
% of nominal V
SOURCE
V
SAT
Note 1.
Note 2.
Note 3.
Note 4.
Note 5.
Exceeding the absolute maximum rating may damage the device.
The device is not guaranteed to function outside its operating rating.
Devices are ESD sensitive. Handling precautions recommended.
Test configuration. External MOSFET not used.
Specification for packaged product only.
MIC5156/5157/5158
4
August 2005
MIC5156/5157/5158
Micrel, Inc.
Typical Characteristics
3.3V Regulator Output
Voltage vs. Temperature
OUTPUT VOLTAGE (V)
3.34
OUTPUT VOLTAGE (V)
5.04
5.03
5.01
5.00
4.99
4.98
4.97
5.02
5.0V Regulator Output
Voltage vs. Temperature
12
10
VOLTAGE (V)
MIC5157/8 Turn-On
Response Time for 3.3V
MOSFET = IRF540
V
IN
= 5V, I
L
= 0.5A
C
C 1
= C
C 2
= 0.1µF
C
C P
= 1µF
C
L
= 50µF
3.33
3.32
3.31
3.30
3.29
3.28
3.27
3.26
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
8
6
4
2
0
LOGIC
INPUT
3.3V
OUTPUT
4.96
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
-2
-0.2
0.0
0.2
0.4
TIME (ms)
0.6
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
OFF-STATE SUPPLY CURRENT (µA)
ON-STATE SUPPLY CURRENT (mA)
ON-STATE SUPPLY CURRENT (mA)
MIC5157/8 On-State Supply
Current vs. Supply Voltage
MIC5157/8 On-State Supply
Current vs. Temperature
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
Off-State Supply Current
vs. Temperature
V
DD
= 5V
V
DD
= 5V
0
10 15 20 25
5
SUPPLY VOLTAGE (V)
30
0.0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
0.0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
CHARGE PUMP VOLTAGE (V)
60
50
40
30
20
10
0
Charge-Pump Output Voltage
vs. Supply Voltage
FLAG VOLTAGE (mV)
200
175
150
125
100
75
50
25
Flag Output Voltage
vs. Temperature
V
DD
= 5V
I
F LAG
= 1mA
1.0
0.9
FLAG VOLTAGE (V)
Flag Output Voltage
vs. Flag Current
V
DD
= 5V
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0
10 15 20 25
5
SUPPLY VOLTAGE (V)
30
0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
0
10
2
4
6
8
FLAG SINK CURRENT (mA)
ENABLE THRESHOLD VOLTAGE (V)
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
ENABLE BIAS CURRENT (µA)
1.8
120
100
80
60
40
20
0
CURRENT LIMIT THRESHOLD (mV)
Enable Threshold Voltage
vs. Temperature
Enable Input Bias Current
vs. Enable Voltage
70
60
50
40
30
20
10
Current Limit Threshold
vs. Temperature
0
2
4 6 8 10 12 14 16
ENABLE VOLTAGE (V)
0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
August 2005
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MIC5156/5157/5158