MIC5247
Micrel, Inc.
MIC5247
150mA Low-Voltage
µCap
Linear Regulator
General Description
The MIC5247 is an efficient and precise, low-voltage CMOS
voltage regulator optimized for ultra-low noise applications.
The MIC5247 offers better than 1% initial accuracy and
85µA constant ground current over load (typically 85µA).
The MIC5247 provides a very low-noise output, ideal for
RF applications where quiet voltage sources are required.
A noise bypass pin is also available for further reduction of
output noise.
Designed specifically for handheld and battery-powered de-
vices, the MIC5247 provides a logic compatible enable pin.
When disabled, power consumption drops nearly to zero.
The MIC5247 also works with low-ESR ceramic capacitors,
reducing the amount of board space necessary for power
applications, critical in handheld wireless devices.
Key features include current limit, thermal shutdown, a push-
pull output for faster transient response, and an active clamp
to speed up device turnoff. Available in the 6-pin 2mm
×
2mm
MLF™ package and the IttyBitty
®
SOT-23-5 package, the
MIC5247 also offers a range of fixed output voltages.
All support documentation can be found on Micrel’s web site
at www.micrel.com.
Features
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Ultra-low noise
Low-voltage outputs
Load independent, ultra-low ground current: 85µA
150mA output current
Current limiting
Thermal shutdown
Tight load and line regulation
“Zero” off-mode current
Stability with low-ESR capacitors
Fast transient response
Logic-controlled enable input
Cellular phones and pagers
Cellular accessories
Battery-powered equipment
Laptop, notebook, and palmtop computers
PCMCIA V
CC
and V
PP
regulation/switching
Consumer/personal electronics
SMPS post-regulator/DC-to-DC modules
High-efficiency linear power supplies
Applications
Typical Application
V
IN
MIC5247-x.xBM5
1
2
Enable
Shutdown
5
V
OUT
C
OUT
ENABLE
SHUTDOWN
V
IN
EN
MIC5247-x.xBML
1
2
3
6
5
4
V
OUT
C
BYP
C
OUT
3
4
(optional)
EN
EN (pin 3) may be
connected directly
to IN (pin 1).
C
BYP
(optional)
Ultra-Low-Noise Regulator Application
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
February 2006
1
M9999-022406
MIC5247
Micrel, Inc.
Ordering Information
Part Number
Standard
MIC5247-1.5BM5
MIC5247-1.6BM5
MIC5247-1.8BM5
MIC5247-1.85BM5
MIC5247-2.0BM5
MIC5247-2.1BM5
MIC5247-2.2BM5
MIC5247-2.4BM5
MIC5247-1.8BD5
MIC5247-2.0BD5
MIC5247-1.5BML
MIC5247-1.6BML
MIC5247-1.8BML
MIC5247-1.85BML
Marking
LU15
LU16
LU18
LU1J
LU20
LU21
LU22
LU24
NU18
NU20
U15
U16
U18
U1J
Pb-Free
MIC5247-1.5YM5
MIC5247-1.6YM5
MIC5247-1.8YM5
MIC5247-1.85YM5
MIC5247-2.0YM5
MIC5247-2.1YM5
MIC5247-2.2YM5
MIC5247-2.4YM5
MIC5247-1.8YD5
MIC5247-2.0YD5
MIC5247-1.5YML
MIC5247-1.6YML
MIC5247-1.8YML
MIC5247-1.85YML
Marking**
LU15
LU16
LU18
LU1J
LU20
LU21
LU22
LU24
NU18
NU20
U15
U16
U18
U1J
Voltage*
1.5V
1.6V
1.8V
1.85V
2.0V
2.1V
2.2V
2.4V
1.8V
2.0V
1.5V
1.6V
1.8V
1.85V
Junction
Temp. Range
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
Package
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
Thin SOT-23-5
Thin SOT-23-5
6-Pin 2mm x 2mm MLF™
6-Pin 2mm x 2mm MLF™
6-Pin 2mm x 2mm MLF™
6-Pin 2mm x 2mm MLF™
* Other voltage options available, please contact Micrel Marketing for details.
** Over and under bar ( ) (__) symbols may not be to scale.
Pin Configuration
EN
GND
IN
3
2
1
EN 1
GND 2
6 BYP
5 NC
4 OUT
LUxx/
NUxx
4
5
IN 3
BYP
OUT
MIC5247-x.xBM5 / YM5
MIC5247-x.xBD5 / YM5
(Top View)
MIC5247-x.xBML / YML
6-Pin 2mm
×
2mm MLF™ (ML)
(Top View)
Pin Description
Pin Number
SOT-23-5
1
2
3
4
5
—
—
Pin Number
MLF™-6
3
2
1
6
4
5
EP
Pin Name
IN
GND
EN
BYP
OUT
NC
GND
Pin Function
Supply input.
Ground.
Enable/Shutdown (Input): CMOS-compatible input. Logic high = enable;
logic low = shutdown. Do not leave open.
Reference bypass: Connect external 0.01pF capacitor to GND to reduce
output noise. May be left open.
Regulator output.
No internal connection.
Ground. Internally connected to the exposed pad. Connect to ground pin.
M9999-022406
2
February 2006
MIC5247
Micrel, Inc.
Absolute Maximum Ratings
(1)
Supply Input Voltage (V
IN
) ....................................0V to +7V
Enable Input Voltage (V
EN
) ...................................0V to V
IN
Junction Temperature (T
J
) ....................................... +150°C
Storage Temperature (T
S
) ........................ –65°C to +150°C
Lead Temperature (soldering, 5 sec.) ........................ 260°C
ESD Rating
(3)
Operating Ratings
(2)
Input Voltage (V
IN
) .......................................... +2.7V to +6V
Enable Input Voltage (V
EN
) ...................................0V to V
IN
Junction Temperature (T
J
) ........................ –40°C to +125°C
Package Thermal Resistance
SOT-23-5 (θ
JA
) .................................................. 235°C/W
2mm
×
2mm MLF™ (θ
JA
) .................................... 90°C/W
Electrical Characteristics
(4)
V
IN
= V
OUT
+ 1.0V; V
IN
= V
EN
; I
OUT
= 100µA; T
J
= 25°C,
bold
values indicate –40°C ≤ T
J
≤ +125°C; unless noted.
Symbol
Parameter
Conditions
Min
–1
–2
–0.3
2
3
150
0.2
85
85
50
160
300
30
1
150
150
V
O
ΔV
LNR
ΔV
LDR
V
IN
– V
OUT
I
Q
I
GND
PSRR
I
LIM
e
n
Output Voltage Accuracy
Line Regulation
Load Regulation
Load Regulation for 1.5V and 1.6V
Dropout Voltage
Quiescent Current
Ground Pin
Current
(7)
I
OUT
= 0mA
V
IN
= 2.7V to 6V
Typ
Max
1
2
+0.3
3
4
Units
%
%
%/V
%
%
mV
µA
µA
µA
dB
mA
µVrms
I
OUT
= 0.1mA to 150mA
(5)
I
OUT
= 150mA
(6)
I
OUT
= 0mA
I
OUT
= 0.1mA to 150mA, V
OUT
= 1.5V or 1.6V
V
EN
≤ 0.4V (shutdown)
I
OUT
= 150mA
f ≤ 1kHz
V
OUT
= 0V
Power Supply Rejection
Current Limit
Output Voltage Noise
C
OUT
= 10µF, C
BYP
= 0.01µF,
f = 10Hz to 100kHz
V
IN
= 2.7V to 5.5V, regulator shutdown
Enable Input
V
IL
Enable Input Logic-Low Voltage
Enable Input Logic-High Voltage
Enable Input Current
Shutdown Resistance Discharge
Thermal Protection
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
Notes:
1. Exceeding the absolute maximum ratings may damage the device.
2. The device is not guaranteed to function outside its operating ratings.
3. Devices are ESD sensitive. Handling precautions recommended.
4. Specification for packaged product only.
5. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range
from 0.1mA to 150mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
6. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value measured a1V differential.
For outputs below 2.7V, dropout voltage is the input-to-output voltage differential with the minimum input voltage 2.7V. Minimum input operating volt-
age is 2.7V.
7. Ground pin current is the regulator quiescent current plus pass transistor base current. The total current drawn from the supply is the sum of the load
current plus the ground pin current.
0.8
1.6
1
0.01
0.01
500
150
10
0.4
V
V
µA
µA
Ω
°C
°C
V
IH
I
EN
V
IN
= 2.7V to 5.5V, regulator enabled
V
IH
≥ 1.6V
V
IL
≤ 0.4V
February 2006
3
M9999-022406
MIC5247
Micrel, Inc.
Typical Characteristics
Power Supply Rejection
Ratio
C
BYP
= 0.01µF
PSRR (dB)
90
70
PSRR (dB)
80 C
BYP
= 1µF
60 C
50
40
30
20
10
1x10
1
1x10
2
70
60
Power Supply Rejection
Ratio
1µF
60
50
PSRR (dB)
Power Supply Rejection
Ratio
0.01µF
1µF
BYP
=0
50 0.01µF
40
C
BYP
= 0
I = 50mA
20
L
V
IN
= 3.4V
10 V
OUT
= 2.4V
C
OUT
=10µF Ceramic
0
30
1x10
1
1x10
3
1x10
4
1x10
2
40
30
C
BYP
= 0
1x10
4
1x10
4
1x10
6
1x10
3
1x10
5
1x10
5
1x10
6
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
60
50
Power Supply Rejection
Ratio
0.01 F
1 F
C
BYP
= 0
OUTPUT SPECTRAL NOISE DENSITY ( V/rt Hz)
1x10
-5
Noise Performance
C
BYP
= 0
75
GROUND CURRENT (µA)
Ground Current
vs. Output Current
74
73
72
71
70
V
IN
= V
OUT
+ 1
1x10
0
1x10
1
1x10
3
1x10
2
PSRR (dB)
40
30
1x10
-6
C
BYP
= 0.01 F
V
IN
= 2.8V
V
OUT
= 1.8V
C
OUT
= 4.7 F
FREQUENCY (Hz)
1x10
20 I
L
= 150mA
V
IN
= 3.4V
10 V
OUT
= 2.4V
C
OUT
= 10 F Ceramic
0
10 100 1k
10k 100k 1M
1x10
-7
1x10
-8
10
I
LOAD
= 50mA
1k 10k 100k 1M
100
FREQUENCY (Hz)
-1
OUTPUT CURRENT (mA)
100
Ground Pin Current
GROUND CURRENT (µA)
100
80
60
40
20
Ground Pin Current
GROUND CURRENT (µA)
100
80
60
40
20
0
0
Ground Pin Current
GROUND CURRENT (µA)
80
60
40
20
I
LOAD
= 100µA
0
-40 -10 20 50 80 110 140
TEMPERATURE °C)
(
I
LOAD
= 150mA
0
-40 -10 20 50 80 110 140
TEMPERATURE °C)
(
I
LOAD
= 100µA
2
3
1
INPUT VOLTAGE (V)
4
VOLTAGE OUT (V)
80
60
40
20
0
0
I
LOAD
= 150mA
1
2
3
INPUT VOLTAGE (V)
4
I
LOAD
= 100µA
I
LOAD
=
150mA
2
1
SHORT CIRCUIT CURRENT (mA)
100
Ground Pin Current
3
Dropout Characteristics
500
400
300
200
100
Short Circuit Current
vs. Temperature
GROUND CURRENT (µA)
0
0
1
2
3
INPUT VOLTAGE (V)
4
VOUT = 0
0
-40 -10 20 50 80 110 140
TEMPERATURE °C)
(
M9999-022406
4
February 2006
1x10
6
1x10
2
1x10
3
1x10
5
1x10
0
I
L
= 100µA
V
IN
= 3.4V
V
OUT
= 2.4V
C
OUT
= 10µF Ceramic
20 I
L
= 100mA
V
IN
= 3.4V
10 V
OUT
= 2.4V
C
OUT
= 10µF Ceramic
0
1
MIC5247
Micrel, Inc.
Typical Characteristics, cont.
2.5
OUTPUT VOLTAGE (V)
Output Voltage
vs. Temperature
200
150
TIME (µs)
Turn-On Time
vs. Bypass Capacitance
C
OUT
= 10µF
I
LOAD
= 100mA
2.4
100
50
Rise Time
1x10
-5
1x10
-4
1x10
-3
1x10
-2
(µF)
BYPASS CAPACITOR
February 2006
5
1x10
-1
1x10
0
1x10
1
2.3
-40 -10 20 50 80 110 140
TEMPERATURE °C)
(
I
LOAD
= 100µA
Prop Delay
0
M9999-022406