MIC5206
150mA Low-Noise LDO Regulator
Micrel Mini 8 is a 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 2006
M9999-051506
(408) 955-1690
General Description
The MIC5206 is an efficient linear voltage regulator with
very low dropout voltage (typically 17mV at light loads and
165mV at 150mA), and very low ground current (600µA at
100mA output), with better than 1% initial accuracy. It has
a logic compatible enable/shutdown control input and an
internal undervoltage monitor.
Designed especially for hand-held, battery-powered
devices, the MIC5206 can be switched by a CMOS or TTL
compatible logic signal. When disabled, power
consumption drops nearly to zero. Dropout ground current
is minimized to prolong battery life.
Key features include an undervoltage monitor with an error
flag output, a reference bypass pin to improve its already
low-noise performance (8-pin versions only), reversed-
battery protection, current limiting, and overtemperature
shutdown.
The MIC5206 is available in several fixed voltages in a tiny
SOT-23-5 package. It features a pinout, similar to the
LP2980, but has significantly better performance. Fixed
and adjustable output voltage versions, featuring the
reference bypass option, are available in the 8-pin Micrel
Mini 8™ 8-pin MSOP (micro small-outline package).
For low-dropout regulators that are stable with ceramic
output capacitors, see the µCap MIC5245/6/7 family.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Features
• Error flag indicates undervoltage fault
• High output voltage accuracy
• Guaranteed 150mA output
• Ultra-low-noise output (8-pin versions)
• Low quiescent current
• Low dropout voltage
• Extremely tight load and line regulation
• Very low temperature coefficient
• Current and thermal limiting
• Reversed-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
Typical Application
SOT-23-5 Fixed Voltage Application
Adjustable Voltage Application
Micrel, Inc. MIC5206
May 2006
2 M9999-051506
(408) 955-1690
Ordering Information
Part Number
Standard Marking Pb-Free Marking
Voltage* Junction Temp. Range Package
MIC5206-2.5BM5 LD25 MIC5206-2.5YM5 LD25 2.5V –40° to +125°C 5-Pin SOT-23
MIC5206-2.7BM5 LD27 MIC5206-2.7YM5 LD27 2.7V –40° to +125°C 5-Pin SOT-23
MIC5206-3.0BM5 LD30 MIC5206-3.0YM5 LD30 3.0V –40° to +125°C 5-Pin SOT-23
MIC5206-3.2BM5 LD32 MIC5206-3.2YM5 LD32 3.2V –40° to +125°C 5-Pin SOT-23
MIC5206-3.3BM5 LD33 MIC5206-3.3YM5 LD33 3.3V –40° to +125°C 5-Pin SOT-23
MIC5206-3.6BM5 LD36 MIC5206-3.6YM5 LD36 3.6V –40° to +125°C 5-Pin SOT-23
MIC5206-3.8BM5 LD38 MIC5206-3.8YM5 LD38 3.8V –40° to +125°C 5-Pin SOT-23
MIC5206-4.0BM5 LD40 MIC5206-4.0YM5 LD40 4.0V –40° to +125°C 5-Pin SOT-23
MIC5206-5.0BM5 LD50 MIC5206-5.0YM5 LD50 5.0V –40° to +125°C 5-Pin SOT-23
MIC5206BMM MIC5206YMM ADJ –40° to +125°C 8-Pin MSOP
MIC5206-3.0BMM MIC5206-3.0YMM 3.0V –40° to +125°C 8-Pin MSOP
MIC5206-3.3BMM MIC5206-3.3YMM 3.3V –40° to +125°C 8-Pin MSOP
MIC5206-3.6BMM MIC5206-3.6YMM 3.6V –40° to +125°C 8-Pin MSOP
MIC5206-3.8BMM MIC5206-3.8YMM 3.8V –40° to +125°C 8-Pin MSOP
MIC5206-4.0BMM MIC5206-4.0YMM 4.0V –40° to +125°C 8-Pin MSOP
MIC5206-5.0BMM MIC5206-5.0YMM 5.0V –40° to +125°C 8-Pin MSOP
* Other voltages available. Contact Micrel for details.
Micrel, Inc. MIC5206
May 2006
3 M9999-051506
(408) 955-1690
Pin Configur ation
MIC5206-xxBM5/YM5
(Fixed Output Voltage)
MIC5206-xxBMM/YMM
(Fixed Output Voltage)
MIC5206-BMM/YMM
(Adjustable Output Voltage)
Pin Description
Pin Number
SOT-23-5 Pin Number
MSOP-8 Pin Name Pin Function
1 8 IN Supply Input
2 4, 6 GND Ground
3 7 EN
Enable/Shutdown (Input): CMOS compatible input. Logic high = enable,
logic low or open = shutdown. Do not leave floating.
4 3 FLAG
Error Flag (Output): Open-collector output. Active low indicates an output
undervoltage condition
5 (fixed) BYP
Reference Bypass: Connect external 470pF capacitor to GND to reduce output
noise. May be left open
5 (adj.) ADJ
Adjust (Input): Adjustable regulator feedback input. Connect to resistor voltage
divider.
5 1, 2 OUT Regulator Output
Micrel, Inc. MIC5206
May 2006
4 M9999-051506
(408) 955-1690
Absolute Maximum Ratings(1)
Supply Input Voltage (V
IN
).............................. –20V to +20V
Enable Input Voltage (V
EN
)............................. –20V to +20V
Power Dissipation (P
D
) .......................... Internally Limited
(3)
Junction Temperature (T
J
) ........................–40°C to +125°C
Lead Temperature (soldering, 5 sec)......................... 260°C
Operating Ratings(2)
Supply Input Voltage (V
IN
)............................. +2.5V to +16V
Enable Input Voltage (V
EN
)..................................... 0V to V
IN
Junction Temperature ...............................–40°C to +125°C
SOT-23-5 (θ
JA
)
(3)
MSOP-8 (θ
JA
)
(3)
Electrical Characteristics
V
IN
= V
OUT
+ 1V; I
L
= 100µA; C
L
= 1.0µF; V
EN
≥ 2.0V; T
J
= 25°C, bold values indicate –40°C < T
J
< +125°C, unless noted.
Symbol Parameter Condition Min Typ Max Units
V
O
Output Voltage Accuracy Variation from nominal V
OUT
–1
–2
1
2
%
%
∆V
O
/∆T Output Voltage Temperature
Coefficient
Note 4 40 ppm/°C
∆V
O
/V
O
Line Regulation V
IN
= V
OUT
+ 1V to 16V
∆V
O
/V
O
Load Regulation I
L
= 0.1mA to 150mA, Note 5
V
IN
– V
O
Dropout Voltage, Note 6 I
L
= 100µA
I
L
= 50mA
I
L
= 100mA
I
L
= 150mA
17
110
140
165
50
70
150
230
250
300
275
350
mV
mV
mV
mV
mV
mV
mV
mV
I
GND
Quiescent Current V
EN
≤ 0.4V (shutdown)
V
EN
≤ 0.18V (shutdown)
0.01 1
5
µA
µA
I
GND
Ground Pin Current, Note 7 V
EN
≥ 2.0V, I
L
= 100µA
I
L
= 50mA
I
L
= 100mA
I
L
= 150mA
80
350
600
1300
125
150
600
800
1000
1500
1900
2500
µA
µA
µA
µA
µA
µA
µA
µA
PSRR Ripple Rejection 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
= 4.7µF, 470pF from BYP to
GND (MM package only)
260 nV√Hz
Enable Input
V
IL
Enable Input Logic-Low Voltage Regulator shutdown 0.4
0.18
V
V
V
IH
Enable Input Logic-High
Voltage
Regulator enable 2.0 V
I
IL
I
IH
Enable Input Current V
IL
≤ 0.4V
V
IL
≤ 0.18V
V
IH
≥ 2.0V
V
IH
≥ 2.0V
0.01
5
–1
–2
20
25
µA
µA
µA
µA
Micrel, Inc. MIC5206
May 2006
5 M9999-051506
(408) 955-1690
Symbol Parameter Condition Min Typ Max Units
Error Flag Output
V
ERR
Flag Threshold Undervoltage condition (below nominal)
Note 9
–2 –6 –10 %
V
OL
Output Logic-Low Voltage I
L
= 1mA, undervoltage condition 0.2 0.4 V
I
FL
Flag Leakage Current Flag off, V
FLAG
= 0V to 16V –1 0.1 +1 µA
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. The maximum allowable power dissipation at any T
A
(ambient temperature) is P
D(max)
= (T
J(max)
–T
A
) / θ
JA
. Exceeding the maximum allowable power
dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The θ
JA
of theMIC5205-x.xBM5 (all versions) is
220°C/W, and the MIC5206-x.xBMM (all versions) is 200°C/W, mounted on a PC board (see “Thermal Considerations” for further details).
4. Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
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 at 1Vdifferential.
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.
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.
9. The error flag comparator includes 3% hysteresis.
Micrel, Inc. MIC5206
May 2006
6 M9999-051506
(408) 955-1690
Typical Characteristics
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100µA
C
OUT
= 1µF
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
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100µA
C
OUT
= 2.2µF
C
BYP
= 0.01µF
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
)Bd(NOITCEJERELPPIR
VOLTAGE DROP (V)
Power Supply Ripple Rejection
vs. Voltage Drop
I
OUT
= 100mA
10mA
1mA
C
OUT
= 1µF
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 1mA
C
OUT
= 1µF
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
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 1mA
C
OUT
= 2.2µF
C
BYP
= 0.01µF
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
)Bd(NOITCEJERELPPIR
VOLTAGE DROP (V)
Power Supply Ripple Rejection
vs. Voltage Drop
I
OUT
= 100mA
10mA
1mA
C
OUT
= 2.2µF
C
BYP
= 0.01µF
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 10mA
C
OUT
= 1µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M -100
-80
-60
-40
-20
0
1E+1 1E+2 1E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 10mA
C
OUT
= 2.2µF
C
BYP
= 0.01µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M 10
100
1000
10000
10 100 1000 10000
(EMITµ)s
CAPACITANCE (pF)
Turn-On Time
vs. Bypass Capacitance
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100mA
C
OUT
= 1µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M -100
-80
-60
-40
-20
0
1E+1 1E+2 1E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Power Supply
Rejection Ratio
I
OUT
= 100mA
C
OUT
= 2.2µF
C
BYP
= 0.01µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M 0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+
7
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10 100 1k 10k 100k 1M 10M
1mA
C
OUT
= 1µF
C
BYP
= 10nF
10mA, C
OUT
= 1µF
V
OUT
= 5V
Micrel, Inc. MIC5206
May 2006
7 M9999-051506
(408) 955-1690
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
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10 100 1k 10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10µF
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
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10 100 1k 10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 22µF
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
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10 100 1k 10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10µF
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
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10 100 1k 10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10µF
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
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10 100 1k 10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10µF
electrolytic
C
BYP
= 1nF
0
40
80
120
160
200
240
280
320
0 40 80 120 160
)Vm(EGATLOVTUOPORD
OUTPUT CURRENT (mA)
Dropout Voltage
vs. Output Current
+125°C
+25°C
–40°C
Micrel, Inc. MIC5206
May 2006
8 M9999-051506
(408) 955-1690
Application Information
Enable/Shutdown
Forcing EN (enable/shutdown) high (> 2V) enables the
regulator. EN is compatible with CMOS logic gates.
If the enable/shutdown feature is not required, connect
EN (enable) to IN (supply input). Refer to the text with
Figures 1aand 2.
Input Capacitor
A 1µF capacitor should be placed from IN to GND if
there is more than 10 inches of wire between the input
and the ac filter capacitor or if a battery is used as the
input.
Reference Bypass Capaci tor
BYP (reference bypass) is connected to the internal
voltage reference. A 470pF capacitor (C
BYP
) connected
from BYP to GND quiets this reference, providing a
significant reduction in output noise. See Figure 2. C
BYP
reduces the regulator phase margin; when using C
BYP
,
output capacitors of 2.2µF or greater are generally
required to maintain stability.
The start-up speed of the MIC5206 is inversely
proportional to the size of the reference bypass
capacitor. Applications requiring a slow ramp-up of
output voltage should consider larger values of C
BYP
.
Likewise, if rapid turn-on is necessary, consider omitting
C
BYP
.
If output noise is not a major concern, omit C
BYP
and
leave BYP open.
Output Capacitor
An output capacitor is required between OUT and GND
to prevent oscillation. The minimum size of the output
capacitor is dependent upon whether a reference bypass
capacitor is used. 1.0µF minimum is recommended
when C
BYP
is not used (see Figure 2). 2.2µF minimum is
recommended when C
BYP
is 470pF (see Figure 2).
Larger values improve the regulator’s transient
response. The output capacitor value may be increased
without limit.
The output capacitor should have an ESR (effective
series resistance) of about 5Ω or less and a resonant
frequency above 1MHz. Most tantalum or aluminum
electrolytic capacitors are adequate; film types will work,
but are more expensive. Since many aluminum
electrolytics have electrolytes that freeze at about
–30°C, solid tantalums are recommended for operation
below –25°C.
At lower values of output current, less output
capacitance is required for output stability. The capacitor
can be reduced to 0.47µF for current below 10mA or
0.33µF for currents below 1mA.
No-Load Stability
The MIC5205 will remain stable and in regulation with no
load (other than the internal voltage divider) unlike many
other voltage regulators. This is especially important in
CMOS RAM keep-alive applications.
Error Flag Output
The error flag is an open-collector output and is active
(low) when an undervoltage of approximately 5% below
the nominal output voltage is detected. A pull-up resistor
from IN to FLAG is shown in all schematics.
If an error indication is not required, FLAG may be left
open and the pull-up resistor may be omitted.
Enable Pin Ramp and the Error Flag
To prevent indeterminate behavior on the error flag
during power down of the device, ensure that the fall
time of the enable pin signal, from logic high to logic low,
is faster than 100µs.
Fixed Regulator Applications
Figure 1a. Low-Noise Fi xed Voltage Application
EN (pin 3) is shown connected to IN (pin 1) for an
application where enable/shutdown is not required. The
error flag is shown with a 100kΩ pull-up resistor.
Figure 1b. Low-Noise Fixed Voltage Application
Figure 1b is an example of a basic configuration where
the lowest-noise operation is not required. C
OUT
= 1µF
minimum. The error flag is shown with a 47kΩ pull-up
resistor.
Micrel, Inc. MIC5206
May 2006
9 M9999-051506
(408) 955-1690
Ultra-Low-Noise Application
Figure 2. Ultra-Low-Noise Fixed Vo ltag e Application
Figure 2 includes a 470pF capacitor for low-noise
operation and shows EN (pin 7) connected to IN (pin 8)
for an application where enable/shutdown is not
required. The error flag is shown with a 47kΩ pull-up
resistor.
Adjustable Regulator Applications
Figure 3 shows the MIC5206BMM adjustable output
voltage configuration. Two resistors set the output
voltage. The formula for output voltage is:
⎟
⎠
⎞
⎜
⎝
⎛+×= 1
R1
R2
1.242VV
OUT
Resistor values are not critical because ADJ (adjust) has
a high input impedance, but for best results use resistors
of 470kΩ or less. A capacitor from ADJ to ground
provides greatly improved noise performance.
Figure 3. Ultra-Low-Noise Adjustable Voltage Application
Figure 3 also includes a 470pF capacitor for lowest-
noise operation and shows EN (pin 7) connected to IN
(pin 8) for an application where enable/shutdown is not
required. C
OUT
= 2.2µF minimum. The error flag is shown
with a 47kΩ pull-up resistor.
Thermal Considerations
Layout
The MIC5206-x.xBM5 (5-pin SOT-23 package) has the
following thermal characteristics when mounted on a
single layer copper-clad printed circuit board.
Multilayer boards having a ground plane, wide traces
near the pads, and large supply bus lines provide better
thermal conductivity.
PC Board
Dielectric θ
JA
FR4 220°C/W
Ceramic 200°C/W
SOT-23-5 Thermal Char acteristics
The “worst case” value of 220°C/W assumes no ground
plane, minimum trace widths, and a FR4 material board.
The MIC5206-xxBMM (8-pin MSOP) has a thermal
resistance of 200°C/W when mounted on a FR4 board
with minimum trace widths and no ground plane.
PC Board
Dielectric θ
JA
FR4 200°C
MSOP Thermal Characteristics
Nominal Power Dissipation and Die Temperature
The MIC5206-x.xBM5 at a 25°C ambient temperature
will operate reliably at over 450mW power dissipation
when mounted in the “worst case” manner described
above. At an ambient temperature of 40°C, the device
may safely dissipate over 380mW. These power levels
are equivalent to a die temperature of 125°C, the
maximum operating junction temperature for the
MIC5206.
For additional heat sink characteristics, please refer to
Micrel Application Hint 17, “Calculating P.C. Board Heat
Sink Area For Surface Mount Packages”.
Micrel, Inc. MIC5206
May 2006
10 M9999-051506
(408) 955-1690
Package Information
5-Pin SOT-23 (M5)
8-Pin MSOP (MM)
Micrel, Inc. MIC5206
May 2006
11 M9999-051506
(408) 955-1690
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
The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its
use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
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.
© 2000 Micrel, Incorporated.
