MIC5205
Micrel
June 2000
1
MIC5205
General Description
The MIC5205 is an efficient linear voltage regulator with ultra-
low-noise output, very low dropout voltage (typically 17mV at
light loads and 165mV at 150mA), and very low ground
current (600
A at 100mA output). The MIC5205 offers better
than 1% initial accuracy.
Designed especially for hand-held, battery-powered devices,
the MIC5205 includes a CMOS or TTL compatible enable/
shutdown control input. When shutdown, power consump-
tion drops nearly to zero. Regulator ground current increases
only slightly in dropout, further prolonging battery life.
Key MIC5205 features include a reference bypass pin to
improve its already excellent low-noise performance, re-
versed-battery protection, current limiting, and
overtemperature shutdown.
The MIC5205 is available in fixed and adjustable output
voltage versions in a small SOT-23-5 package.
For low-dropout regulators that are stable with ceramic
output capacitors, see the
Cap MIC5245/6/7 family.
Ordering Information
Part Number
Marking
Voltage
Accuracy
Junction Temp. Range*
Package
MIC5205BM5
LBAA
Adj
1%
40
C to +125
C
SOT-23-5
MIC5205-2.5BM5
LB25
2.5V
1%
40
C to +125
C
SOT-23-5
MIC5205-2.7BM5
LB27
2.7V
1%
40
C to +125
C
SOT-23-5
MIC5205-2.8BM5
LB28
2.8V
1%
40
C to +125
C
SOT-23-5
MIC5205-2.85BM5
LB2J
2.85V
1%
40
C to +125
C
SOT-23-5
MIC5205-2.9BM5
LB29
2.9V
1%
40
C to +125
C
SOT-23-5
MIC5205-3.0BM5
LB30
3.0V
1%
40
C to +125
C
SOT-23-5
MIC5205-3.3BM5
LB33
3.3V
1%
40
C to +125
C
SOT-23-5
MIC5205-3.6BM5
LB36
3.6V
1%
40
C to +125
C
SOT-23-5
MIC5205-3.8BM5
LB38
3.8V
1%
40
C to +125
C
SOT-23-5
MIC5205-4.0BM5
LB40
4.0V
1%
40
C to +125
C
SOT-23-5
MIC5205-5.0BM5
LB50
5.0V
1%
40
C to +125
C
SOT-23-5
Other voltages available. Contact Micrel for details.
Typical Application
1
5
2
3
4
C
OUT
= 2.2F
tantalum
C
BYP
Enable
Shutdown
EN
V
OUT
Low-Noise Operation:
C
BYP
= 470pF, C
OUT
2.2F
Basic Operation:
C
BYP
= not used, C
OUT
1F
MIC5205-x.xBM5
EN (pin 3) may be
connected directly
to IN (pin 1).
V
IN
Ultra-Low-Noise Regulator Application
MIC5205
150mA Low-Noise LDO Regulator
Features
Ultra-low-noise output
High output voltage accuracy
Guaranteed 150mA output
Low quiescent current
Low dropout voltage
Extremely tight load and line regulation
Very low temperature coefficient
Current and thermal limiting
Reverse-battery protection
"Zero" off-mode current
Logic-controlled electronic enable
Applications
Cellular telephones
Laptop, notebook, and palmtop computers
Battery-powered equipment
PCMCIA V
CC
and V
PP
regulation/switching
Consumer/personal electronics
SMPS post-regulator/dc-to-dc modules
High-efficiency linear power supplies
Micrel, Inc. 1849 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 944-0970 http://www.micrel.com
MIC5205
Micrel
MIC5205
2
June 2000
Pin Configuration
IN
OUT
BYP
EN
LBxx
Part
Identification
1
3
4
5
IN
OUT
ADJ
EN
LBAA
1
3
4
5
2
2
GND
GND
MIC5205-x.xBM5
MIC5205BM5
Fixed Voltages
Adjustable Voltage
Absolute Maximum Ratings
(Note 1)
Supply Input Voltage (V
IN
) ............................ 20V to +20V
Enable Input Voltage (V
EN
) ........................... 20V to +20V
Power Dissipation (P
D
) ............... Internally Limited, Note 3
Lead Temperature (soldering, 5 sec.) ....................... 260
C
Junction Temperature (T
J
) ....................... 40
C to +125
C
Storage Temperature (T
S
) ....................... 65
C to +150
C
Operating Ratings
(Note 2)
Input Voltage (V
IN
) ....................................... +2.5V to +16V
Enable Input Voltage (V
EN
) .................................. 0V to V
IN
Junction Temperature (T
J
) ....................... 40
C to +125
C
Thermal Resistance, SOT-23-5
(
JA
) ....................... Note 3
Pin Description
MIC5205-x.x
MIC5205
Pin Name
Pin Function
(fixed)
(adjustable)
1
1
IN
Supply Input
2
2
GND
Ground
3
3
EN
Enable/Shutdown (Input): CMOS compatible input. Logic high = enable,
logic low or open = shutdown.
4
BYP
Reference Bypass: Connect external 470pF capacitor to GND to reduce
output noise. May be left open.
4
ADJ
Adjust (Input): Adjustable regulator feedback input. Connect to resistor
voltage divider.
5
5
OUT
Regulator Output
MIC5205
Micrel
June 2000
3
MIC5205
Electrical Characteristics
V
IN
= V
OUT
+ 1V; I
L
= 100
A; C
L
= 1.0
F; V
EN
2.0V; T
J
= 25
C, bold values indicate 40
C
T
J
+125
C; unless noted.
Symbol
Parameter
Conditions
Min
Typical
Max
Units
V
O
Output Voltage Accuracy
variation from specified V
OUT
1
1
%
2
2
%
V
O
/
T
Output Voltage
Note 4
40
ppm/
C
Temperature Coefficient
V
O
/V
O
Line Regulation
V
IN
= V
OUT
+ 1V to 16V
0.004
0.012
% / V
0.05
% / V
V
O
/V
O
Load Regulation
I
L
= 0.1mA to 150mA, Note 5
0.02
0.2
%
0.5
%
V
IN
V
O
Dropout Voltage, Note 6
I
L
= 100
A
10
50
mV
70
mV
I
L
= 50mA
110
150
mV
230
mV
I
L
= 100mA
140
250
mV
300
mV
I
L
= 150mA
165
275
mV
350
mV
I
GND
Quiescent Current
V
EN
0.4V (shutdown)
0.01
1
A
V
EN
0.18V (shutdown)
5
A
I
GND
Ground Pin Current, Note 7
V
EN
2.0V, I
L
= 100
A
80
125
A
150
A
I
L
= 50mA
350
600
A
800
A
I
L
= 100mA
600
1000
A
1500
A
I
L
= 150mA
1300
1900
A
2500
A
PSRR
Ripple Rejection
frequency = 100Hz, I
L
= 100
A
75
dB
I
LIMIT
Current Limit
V
OUT
= 0V
320
500
mA
V
O
/
P
D
Thermal Regulation
Note 8
0.05
%/W
e
no
Output Noise
I
L
= 50mA, C
L
= 2.2
F,
260
nV/ Hz
470pF from BYP to GND
ENABLE Input
V
IL
Enable Input Logic-Low Voltage
regulator shutdown
0.4
V
0.18
V
V
IH
Enable Input Logic-High Voltage
regulator enabled
2.0
V
I
IL
Enable Input Current
V
IL
0.4V
0.01
1
A
V
IL
0.18V
2
A
I
IH
V
IH
2.0V
2
5
20
A
V
IH
2.0V
25
A
Note 1.
Exceeding the absolute maximum rating may damage the device.
Note 2.
The device is not guaranteed to function outside its operating rating.
Note 3:
The maximum allowable power dissipation at any T
A
(ambient temperature) is P
D(max)
= (T
J(max)
T
A
)
JA
. Exceeding the maximum
allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The
JA
of the MIC5205-
xxBM5 (all versions) is 220
C/W mounted on a PC board (see "Thermal Considerations" section for further details).
Note 4:
Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Note 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.
Note 6:
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.
Note 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.
Note 8:
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 150mA load pulse at V
IN
= 16V for t = 10ms.
MIC5205
Micrel
MIC5205
4
June 2000
Typical Characteristics
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100
A
C
OUT
= 1
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100
A
C
OUT
= 2.2
F
C
BYP
= 0.01
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
0
10
20
30
40
50
60
0
0.1
0.2
0.3
0.4
RIPPLE REJECTION (dB)
VOLTAGE DROP (V)
Power Supply Ripple Rejection
vs. Voltage Drop
I
OUT
= 100mA
10mA
1mA
C
OUT
= 1
F
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 1mA
C
OUT
= 1
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 1mA
C
OUT
= 2.2
F
C
BYP
= 0.01
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
0
10
20
30
40
50
60
70
80
90
100
0
0.1
0.2
0.3
0.4
RIPPLE REJECTION (dB)
VOLTAGE DROP (V)
Power Supply Ripple Rejection
vs. Voltage Drop
I
OUT
= 100mA
10mA
1mA
C
OUT
= 2.2
F
C
BYP
= 0.01
F
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 10mA
C
OUT
= 1
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 10mA
C
OUT
= 2.2
F
C
BYP
= 0.01
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
10
100
1000
10000
10
100
1000
10000
TIME (
s)
CAPACITANCE (pF)
Turn-On Time
vs. Bypass Capacitance
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100mA
C
OUT
= 1
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
PSRR (dB)
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100mA
C
OUT
= 2.2
F
C
BYP
= 0.01
F
V
IN
= 6V
V
OUT
= 5V
10
100
1k
10k 100k 1M 10M
0
40
80
120
160
200
240
280
320
0
40
80
120
160
DROPOUT VOLTAGE (mV)
OUTPUT CURRENT (mA)
Dropout Voltage
vs. Output Current
+125
C
+25
C
40
C
MIC5205
Micrel
June 2000
5
MIC5205
Typical Characteristics
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
NOISE (
V/
Hz)
FREQUENCY (Hz)
Noise Performance
10
100
1k
10k 100k 1M 10M
1mA
C
OUT
= 1
F
C
BYP
= 10nF
10mA, C
OUT
= 1
F
V
OUT
= 5V
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
NOISE (
V/
Hz)
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10
100
1k
10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10
F
electrolytic
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
NOISE (
V/
Hz)
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10
100
1k
10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 22
F
tantalum
C
BYP
= 10nF
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
NOISE (
V/
Hz)
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10
100
1k
10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10
F
electrolytic
C
BYP
= 100pF
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
NOISE (
V/
Hz)
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10
100
1k
10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10
F
electrolytic
C
BYP
= 1nF
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
NOISE (
V/
Hz)
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10
1k
100
10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10
F
electrolytic
C
BYP
= 10nF
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