MIC5270
Micrel, Inc.
MIC5270
µ
Cap Negative Low-Dropout Regulator
General Description
The MIC5270 is a
µCap
100mA negative regulator in a
SOT-23-5 package. With better than 2% initial accuracy, this
regulator provides a very accurate supply voltage for applica-
tions that require a negative rail. The MIC5270 sinks 100mA
of output current at very low dropout voltage (600mV maxi-
mum at 100mA of output current).
The
µCap
regulator design is optimized to work with low-
value, low-cost ceramic capacitors. The output typically re-
quires only a 1µF capacitance for stability.
Designed for applications where small packaging and effi-
ciency are critical, the MIC5270 combines LDO design exper-
tise with IttyBitty
®
packaging to improve performance and
reduce power dissipation. Ground current is optimized to help
improve battery life in portable applications.
The MIC5270 is available in the SOT-23-5 package for space
saving applications and it is available with fixed –3.0V, –4.1V,
–5.0V, and adjustable outputs.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Features
•
•
•
•
•
•
•
•
Stable with ceramic or tantalum capacitor
Low dropout voltage: 500mV @ 100mA
Low ground current: 35µA @ load = 100µA
Tight initial accuracy:
±2%
Tight load and line regulation
Thermal shutdown
Current limiting
IttyBitty
®
SOT-23-5 packaging
Applications
•
•
•
•
GaAsFET bias
Portable cameras and video recorders
PDAs
Battery-powered equipment
Ordering Information
Standard
MIC5270BM5
MIC5270-3.0BM5
MIC5270-4.1BM5
MIC5270-5.0BM5
Part Number
Marking Code
PbFree
LLAA
LL30
LL41
LL50
MIC5270YM5
MIC5270-3.0YM5
MIC5270-4.1YM5
MIC5270-5.0YM5
Marking Code
LLAA
LL30
LL41
LL50
Voltage
Adj.
–3.0V
–4.1V
–5.0V
Junction
Temp. Range
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
Package
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
Typical Application
MIC5270-5.0BM5
2
MIC5270BM5
2
R1
R2 V
OUT
–5.0V
V
IN
–6.0V
GND
–IN –OUT
4
5
V
OUT
–5.0V
GND ADJ
–IN
–OUT
3
4
V
IN
–6.0V
5
1µF
10µF
1µF
10µF
Regulator With Fixed Output
Regulator With Adjustable Output
IttyBitty is a registered trademark of Micrel, Inc.
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
May 2005
1
M9999-052705
MIC5270
Micrel, Inc.
Pin Configuration
ADJ GND NC
3
2
1
NC GND NC
3
2
1
LLAA
4
5
4
LLxx
5
–OUT
–IN
–OUT
–IN
MIC5270BM5
Adjustable Voltage
MIC5270-x.xBM5
Fixed Output Voltage
Pin Description
Pin Number
(Adj.)
1
2
Pin Number
(Fixed)
1
2
3
3
4
5
4
5
Pin Name
NC
GND
NC
ADJ
–OUT
–IN
Pin Function
Not internally connected.
Ground.
Not internally connected.
Adjustable (Input): Adjustable feedback output connects to resistor voltage
divider.
Negative Regulator Output.
Negative Supply Input.
M9999-052705
2
May 2005
MIC5270
Micrel, Inc.
Absolute Maximum Ratings
(Note 1)
Input Voltage (V
IN
) ....................................... –20V to +0.3V
Power Dissipation (P
D
) ............................ Internally Limited
Junction Temperature (T
J
) ....................... –40°C to +125°C
Lead Temperature (soldering, 5 sec.) ....................... 260°C
Storage Temperature (T
S
) ....................... –65°C to +150°C
ESD Rating,
Note 3
Operating Ratings
(Note 2)
Input Voltage (V
IN
) ....................................... –16V to –3.3V
Junction Temperature (T
J
) ....................... –40°C to +125°C
Thermal Resistance (θ
JA
) ........................................
Note 4
Electrical Characteristics
(Note 5)
V
IN
= V
OUT
– 1.0V; C
OUT
= 4.7µF, I
OUT
= 100µA; T
J
= 25°C,
bold
values indicate –40°C
≤
T
J
≤
+125°C; unless noted.
Symbol
V
OUT
∆V
OUT
/∆T
∆V
OUT
/V
OUT
∆V
OUT
/V
OUT
V
IN
– V
OUT
Parameter
Output Voltage Accuracy
Output Voltage Temperature
Coefficient
Line Regulation
Load Regulation
Dropout Voltage,
Note 8
Condition
Variation from nominal V
OUT
Note 6
V
IN
= V
OUT
– 1V to –16V
I
OUT
= 100µA to 100mA,
Note 7
I
OUT
= 100µA
I
OUT
= 50mA
I
OUT
= 100mA
I
GND
Ground Current,
Note 9
I
OUT
= 100µA
I
OUT
= 50mA
I
OUT
= 100mA
PSRR
I
LIMIT
∆V
OUT
/∆P
D
Note 1.
Note 2.
Note 3.
Note 4.
Min
–2
–3
Typ
Max
2
3
Units
%
%
ppm/°C
100
0.05
1.5
40
360
500
35
0.7
2.1
50
160
0.05
300
3.0
500
700
900
100
0.15
0.2
1.8
2.0
%/V
%
%
mV
mV
mV
µA
mA
mA
dB
mA
%/W
Ripple Rejection
Current Limit
Thermal Regulation
f = 120Hz
V
OUT
= 0V
Note 10
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.
The maximum allowable power dissipation is a function of the maximum junction temperature, T
J(max)
, the junction-to-ambient thermal
resistance,
θ
JA
, and the ambient temperature, T
A
. The maximum allowable power dissipation at any ambient temperature is calculated using:
P
D(max)
= (T
J(max)
– T
A
)
÷
θ
JA
, where
θ
JA
is 235°C/W. Exceeding the maximum allowable power dissipation will result in excessive die
temperature, and the regulator will go into thermal shutdown. See the
“Thermal Considerations”
section for details.
Specification for packaged product only.
Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load
range from 100µA to 100mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1V
differential.
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.
Note 5.
Note 6.
Note 7.
Note 8.
Note 9.
Note 10.
Thermal regulation is defined as the change in output voltage at a time “t” after a change in power dissipation is applied, excluding load or line
regulation effects. Specifications are for a 100mA load pulse at V
IN
= –16V for t = 10ms.
May 2005
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M9999-052705
MIC5270
Micrel, Inc.
Typical Characteristics
Dropout
Characteristics
OUTPUT VOLTAGE (V)
-3.5
OUTPUT VOLTAGE (V)
-3.305
-3.3
-3.295
-3.29
-3.285
-3.28
-3.275
-3.27
-3.265
-5
-3.26
0
Output Voltage
vs. Output Current
OUTPUT VOLTAGE (V)
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0 Load
-3.4
-3.38
-3.36
-3.34
-3.32
-3.3
-3.28
Output Voltage
vs. Temperature
-100mA Load
-1
-2
-3
-4
SUPPLY VOLTAGE (V)
-20
-40
-60
-80 -100
OUTPUT CURRENT (mA)
-3.26
-3.24
-3.22
-3.2
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
-2.5
Ground Current
vs. Output Current
GROUND CURRENT (µA)
-90
-80
-70
-60
Ground Current
Characteristics
GROUND CURRENT (mA)
-1mA Load
-2.5
Ground Current
Characteristics
GROUND CURRENT (mA)
-2
-1.5
-1
-0.5
5V
IN
0
0
-20
-40
-60
-80 -100
OUTPUT CURRENT (mA)
-2 -100mA Load
-1.5
-50mA Load
-1
-0.5
0
0
-10mA Load
-50 -100µA Load
-40
-30
-20
-10
0
0
0µA Load
-1
-2
-3
-4
SUPPLY VOLTAGE (V)
-5
-1
-2
-3
-4
SUPPLY VOLTAGE (V)
-5
-30
GROUND CURRENT (µA)
Ground Current
vs. Temperature
GROUND CURRENT (µA)
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
Ground Current
vs. Temperature
ENABLE THRESHOLD (V)
-1.6
-1.4
-1.2
Negative Enable Threshold
vs. Supply Voltage
Enable On
-1mA Load
-25
-20
-15
-10
-5
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
0A Load
-100mA Load
-1
-0.8
-0.6
-0.4
-0.2
0
-4
Enable Off
-50A Load
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
-7
-10
-13
SUPPLY VOLTAGE (V)
-16
-600
Dropout
vs. Output Current
DROPOUT VOLTAGE (mV)
-400
-350
-300
-250
-200
-150
-100
-50
Dropout
vs. Temperature
DROPOUT VOLTAGE (mV)
-10mA Load
-700
-600
-500
-400
-300
-200
-100
Dropout
vs. Temperature
-100mA Load
DROPOUT VOLTAGE (mV)
-500
-400
-300
-200
-100
0
0
-20
-40
-60
-80 -100
OUTPUT CURRENT (mA)
-50mA Load
0A Load
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
0
-40 -20 0 20 40 60 80 100 120
TEMPERATURE (°C)
M9999-052705
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May 2005
MIC5270
Micrel, Inc.
Functional Characteristics
Load Transient
Load Transient
V
OUT
(10mV/div.)
Output Current
(50mA/div.)
-100mA
Output Current
(50mA/div.)
-10mA
V
OUT
(10mV/div.)
C
OUT
= 1µF Ceramic
V
IN
= 5V
V
OUT
= 3V
-10mA
C
OUT
= 1µF Ceramic
V
IN
= 5V
V
OUT
= 3V
-100mA
TIME (2ms/div.)
TIME (2ms/div.)
Negative Enable Transient
0V
V
OUT
(1V/div.)
Enable
(1V/div.)
0V
TIME (20
m
s/div.)
May 2005
5
M9999-052705
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