MIC5207
180mA Low-Noise LDO 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
December 2007
M9999-123107
General Description
The MIC5207 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 (720µA at 100mA output). The MIC5207
offers better than 3% initial accuracy.
Designed especially for hand-held, battery-powered
devices, the MIC5207 includes a CMOS or TTL compatible
enable/shutdown control input. When in shutdown, power
consumption drops nearly to zero.
Key MIC5207 features include a reference bypass pin to
improve its already low-noise performance, reversed-
battery protection, current limiting, and overtemperature
shutdown.
The MIC5207 is available in fixed and adjustable output
voltage versions in a small SOT-23-5 package. Contact
Micrel for details.
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
• Ultra-low-noise output
• High output voltage accuracy
• Guaranteed 180mA output
• 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
Battery-Powered Regu l ator Application
Micrel, Inc. MIC5207
December 2007 2 M9999-123107
Ordering Information
Part Number Marking Voltage* Junction Temp. Range Package Lead Finish
MIC5207-1.8BD5 NE18 1.8V –40° to +125°C 5-Pin Thin SOT-23 Standard
MIC5207BM5 LEAA Adj. –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-1.8BM5 LE18 1.8V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-2.5BM5 LE25 2.5V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-2.8BM5 LE28 2.8V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-3.0BM5 LE30 3.0V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-3.2BM5 LE32 3.2V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-3.3BM5 LE33 3.3V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-3.6BM5 LE36 3.6V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-3.8BM5 LE38 3.8V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-4.0BM5 LE40 4.0V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-5.0BM5 LE50 5.0V –40° to +125°C 5-Pin SOT-23 Standard
MIC5207-3.3BZ*** -- 3.3V –40° to +125°C 3-Pin TO-92 Standard
MIC5207-1.8YD5 NE18** 1.8V –40° to +125°C 5-Pin Thin SOT-23 Pb-Free
MIC5207YM5 LEAA** Adj. –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-1.8YM5 LE18** 1.8V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-2.5YM5 LE25** 2.5V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-2.8YM5 LE28** 2.8V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-2.9YM5 LE29** 2.9V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.0YM5 LE30** 3.0V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.1YM5 LE31** 3.1V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.2YM5 LE32** 3.2V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.3YM5 LE33** 3.3V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.6YM5 LE36** 3.6V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.8YM5 LE38** 3.8V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-4.0YM5 LE40** 4.0V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-5.0YM5 LE50** 5.0V –40° to +125°C 5-Pin SOT-23 Pb-Free
MIC5207-3.3YZ*** -- 3.3V –40° to +125°C 3-Pin TO-92 Pb-Free
* Other voltages available. Contact Micrel for details.
** Under bar ( __ ) symbol may not be to scale.
*** TO-92 Package discontinuance notification issued September 2007. End-of-life-buy offered thru December 31, 2007. Contact factory for
additional information.
Micrel, Inc. MIC5207
December 2007 3 M9999-123107
Pin Configur ation
123
IN GND OUT
(Bottom View)
MIC5207BM5/YM5 (M5)
(Adjustable Voltage)
MIC5207-x.xBM5/YM5 (M5)
MIC5207-x.xBD5/YD5 (D5)
(Fixed Voltage)
MIC5207-x.xBZ/YZ (Z)
(Fixed Voltage)
Pin Description
Pin Number
SOT-23-5 Pin Number
TO-92 Pin Name Pin Function
1 1 IN Supply Input
2 2 GND Ground
3 EN
Enable/Shutdown (Input): CMOS compatible input. Logic high = enable,
logic low or open = shutdown. Do not leave floating.
4 (fixed) BYP Reference Bypass: Connect external 470pF capacitor to GND to reduce output
noise. May be left open. For 1.8V or 2.5V operation, see “Applications
Information.”
4 (adj.) ADJ Adjust (Input): Adjustable regulator feedback input. Connect to resistor voltage
divider.
5 3 OUT Regulator Output
Micrel, Inc. MIC5207
December 2007 4
M9999-123107
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)
Lead Temperature (soldering, 5 sec)......................... 260°C
Junction Temperature (T
J
)
All except 1.8V....................................–40°C to +125°C
1.8V ONLY..............................................0°C to +125°C
Storage Temperature (T
S
).........................–65°C to +150°C
Operating Ratings(2)
Supply Input Voltage (V
IN
)............................. +2.5V to +16V
Enable Input Voltage (V
EN
)..................................... 0V to V
IN
Junction Temperature (T
J
)
All except 1.8V.................................... –40°C to +125°C
1.8V ONLY.............................................. 0°C to +125°C
Thermal Resistance (θ
JA
).......................................... Note 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 except
0°C < T
J
< +125°C for 1.8V, unless noted.
Symbol Parameter Condition Min Typ Max Units
V
O
Output Voltage Accuracy Variation from nominal V
OUT
–3
–4
3
4
%
%
∆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 0.005 0.05
0.10
%/V
%/V
∆V
O
/V
O
Load Regulation I
L
= 0.1mA to 150mA, Note 5 0.05
0.5
0.7
%
%
V
IN
– V
O
Dropout Voltage, Note 6 I
L
= 100µA
I
L
= 50mA
I
L
= 100mA
I
L
= 150mA
17
115
140
165
60
80
175
250
280
325
300
400
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
720
1800
130
170
650
900
1100
2000
2500
3000
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
= 2.2µF,
470pF from BYP to GND
260 nV√Hz
Micrel, Inc. MIC5207
December 2007 5
M9999-123107
Symbol Parameter Condition Min Typ Max Units
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
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 cause excessive die temperature, and the regulator will go into thermal shutdown. The θ
JA
of the SOT-23-5 (M5) is 235°C/W, and the
TO-92 (Z) is 180°C/W (0.4” leads) or 160°C/W (0.25” leads) soldered 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 180mA. 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 180mA load pulse at V
IN
= 16V for t = 10ms.
Micrel, Inc. MIC5207
December 2007 6
M9999-123107
Typical Characteristics
-100
-80
-60
-40
-20
0
1E+11E+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+11E+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
= 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 1000
0
(EMITµ)s
CAPACITANCE (pF)
Turn-On Time
vs. Bypass Capacitance
-100
-80
-60
-40
-20
0
1E+1 1E+2 1E+31E+4 1E+51E+6 1E+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
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. MIC5207
December 2007 7
M9999-123107
Typical Characteristics (continued)
0.0001
0.001
0.01
0.1
1
10
1E+11E+21E+3 1E+4 1E+51E+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
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+61E+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
Micrel, Inc. MIC5207
December 2007 8
M9999-123107
Block Diagrams
Low-Noise Fixed Regulator (TO-92 version only)
Ultra-Low-Noise Fixed Regulator
Ultra-Low-Noise Adjustable Regulator
Micrel, Inc. MIC5207
December 2007 9
M9999-123107
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 (pin 3) to IN (supply input, pin 1). See Figure 1.
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. CBYP reduces the
regulator phase margin; when using CBYP, output
capacitors of 2.2µF or greater are generally required to
maintain stability.
The start-up speed of the MIC5207 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 CBYP is not used (see Figure 2). 2.2µF minimum
is recommended when C
BYP
is 470pF (see Figure 1).
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. Ultra-low-ESR capacitors can
cause a low amplitude oscillation on the output and/or
under-damped transient response. 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 MIC5207 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
CMOSRAM keep-alive applications.
Thermal Considerations
The MIC5207 is designed to provide 180mA of
continuous current in a very small package. Maximum
power dissipation can be calculated based on the output
current and the voltage drop across the part. To
determine the maximum power dissipation of the
package, use the junction-to-ambient thermal resistance
of the device and the following basic equation:
(
)
JA
AJ(MAX)
D(MAX) θ
TT
P−
=
T
J(max)
is the maximum junction temperature of the die,
125°C, and T
A
is the ambient operating temperature. θ
JA
is layout dependent; Table 1 shows examples of
junction-to-ambient thermal resistance for the MIC5207.
Package θ
JA
Recommemded
Minimum Footprint θ
JA
1” Square
Copper Clad θ
J/C
SOT-23-5
(M5)
235°C/W 170°C/W 130°C/W
Table 1. SOT-23-5 Thermal Resistance
The actual power dissipation of the regulator circuit can
be determined using the equation:
(
)
GNDINOUTOUTIND
I VI VVP +
−
=
Substituting P
D(max)
for P
D
and solving for the operating
conditions that are critical to the application will give the
maximum operating conditions for the regulator circuit.
For example, when operating the MIC5207-3.3BM5 at
room temperature with a minimum footprint layout, the
maximum input voltage for a set output current can be
determined as follows:
235
C25C125
P
D(MAX)
°−°
=
425mWP
D(MAX)
=
The junction-to-ambient thermal resistance for the
minimum footprint is 220°C/W, from Table 1. The
maximum power dissipation must not be exceeded for
proper operation. Using the output voltage of 3.3V and
an output current of 150mA, the maximum input voltage
can be determined. From the Electrical Characteristics
table, the maximum ground current for 150mA output
current is 3000µA or 3mA.
(
)
3mAV150mA 3.3V455mW
ININ
⋅
+−
=
3mAV495mW-150mA V455mW
ININ
⋅
+
⋅
=
153mA V920mW
IN
⋅
=
Micrel, Inc. MIC5207
December 2007 10 M9999-123107
6.01VV
IN(MAX)
=
Therefore, a 3.3V application at 150mA of output current
can accept a maximum input voltage of 6V in a SOT-23-
5 package. For a full discussion of heat sinking and
thermal effects on voltage regulators, refer to the
Regulator Thermals section of Micrel’s Designing with
Low-Dropout Voltage Regulators handbook
Low-Voltage Operation
The MIC5207-1.8 and MIC5207-2.5 require special
consideration when used in voltage-sensitive systems.
They may momentarily overshoot their nominal output
voltages unless appropriate output and bypass capacitor
values are chosen.
During regulator power up, the pass transistor is fully
saturated for a short time, while the error amplifier and
voltage reference are being powered up more slowly
from the output (see “Block Diagram”). Selecting larger
output and bypass capacitors allows additional time for
the error amplifier and reference to turn on and prevent
overshoot.
To ensure that no overshoot is present when starting up
into a light load (100µA), use a 4.7µF output capacitance
and 470pF bypass capacitance. This slows the turn-on
enough to allow the regulator to react and keep the
output voltage from exceeding its nominal value. At
heavier loads, use a 10µF output capacitance and
470pF bypass capacitance. Lower values of output and
bypass capacitance can be used, depending on the
sensitivity of the system.
Applications that can withstand some overshoot on the
output of the regulator can reduce the output capacitor
and/or reduce or eliminate the bypass capacitor.
Applications that are not sensitive to overshoot due to
power-on reset delays can use normal output and
bypass capacitor configurations.
Please note the junction temperature range of the
regulator at 1.8V output (fixed and adjustable) is 0˚C to
+125˚C.
Fixed Regulator Applications
Figure 1. Ultra-Low-Noise Fixed Vo ltag e Application
Figure 1 includes a 470pF capacitor for ultra-low-noise
operation and shows EN (pin 3) connected to IN (pin 1)
for an application where enable/shutdown is not
required. C
OUT
= 2.2µF minimum.
Figure 2. Low-Noise Fixed Voltage Application
Figure 2 is an example of a basic low-noise
configuration. C
OUT
= 1µF minimum.
Adjustable Regulator Applications
The MIC5207BM5 can be adjusted to a specific output
voltage by using two external resistors (Figure 3). The
resistors set the output voltage based on the following
equation:
1.242V V,
R1
R2
1VV
REFREFOUT
=
⎟
⎠
⎞
⎜
⎝
⎛+=
This equation is correct due to the configuration of the
bandgap reference. The bandgap voltage is relative to
the output, as seen in the block diagram. Traditional
regulators normally have the reference voltage relative
to ground; therefore, their equations are different from
the equation for the MIC5207BM5.
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 includes the optional 470pF noise bypass
capacitor from ADJ to GND to reduce output noise.
Dual-Supply Operation
When used in dual-supply systems where the regulator
load is returned to a negative supply, the output voltage
must be diode clamped to ground.
USB Application
Figure 4 shows the MIC5207-3.3BZ (3-terminal, TO-92)
in a USB application. Since the V
BUS
supply may be
greater than 10 inches from the regulator, a 1µF input
capacitor is included.
Micrel, Inc. MIC5207
December 2007 11 M9999-123107
Figure 4. Single-Port Self-Powered Hub
Micrel, Inc. MIC5207
December 2007 12 M9999-123107
Package Information
5-Pin SOT-23 (M5)
5-Pin Thin SOT-23 (D5)
Micrel, Inc. MIC5207
December 2007 13 M9999-123107
3
2
1
10° typ.
5° typ.
5° typ.
0.185 (4.699)
0.175 (4.445)
0.185 (4.699)
0.175 (4.445)
0.085 (2.159) Diam.
0.500 (12.70) Min.
0.090 (2.286) typ.
0.0155 (0.3937)
0.0145 (0.3683)
Seat ing Plane
0.025 (0.635) Max
Uncontrolled
Lead Diamet er
0.016 (0.406)
0.014 (0.356)
0.105 (2.667)
0.095 (2.413)
0.055 (1.397)
0.045 (1.143)
0.090 (2.286) Radius, typ.
0.145 (3.683)
0.135 (3.429)
0.055 (1.397)
0.045 (1.143)
BOTTOM VIEW
3-Pin TO-92 (Z)
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.
© 2001 Micrel, Incorporated.
