MICREL MIC5245-3.3BMM, MIC5245-3.3BM5, MIC5245-3.1BM5, MIC5245-2.5BM5, MIC5245-2.7BM5 Datasheet

MIC5245 Micrel

MIC5245

150mA µCap CMOS LDO Regulator

Preliminary Information

General Description

The MIC5245 is an efficient, precise CMOS voltage regulator
optimized for ultra-low-noise applications. The MIC5245 of­fers better than 1% initial accuracy, extremely low dropout
voltage (typically 150mV at 150mA) and constant ground
current over load (typically 100µA). The MIC5245 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 hand-held and battery-powered
devices, the MIC5245 provides a TTL logic compatible en­able pin. When disabled, power consumption drops nearly to
zero.

The MIC5245 also works with low-ESR ceramic capacitors,
reducing the amount of board space necessary for power
applications, critical in hand-held wireless devices.

Key features include current limit, thermal shutdown, a push­pull output for faster transient response, and an active clamp
to speed up device turnoff. Available in the IttyBitty™ SOT-23-5
and power MSO-8 packages, the MIC5245 also offers a
range of fixed output voltages.

Ordering Information

Features

• Ultralow dropout—100mV @ 100mA

• Ultralow noise—30µV(rms)

• Stability with tantalum or ceramic capacitors

• Load independent, ultralow ground current

• 150mA output current

• Current limiting

• Thermal Shutdown

• Tight load and line regulation

•“Zero” off-mode current

• Fast transient response

• TTL-Logic-controlled enable input

Applications

• Cellular phones and pagers

• Cellular accessories

• Battery-powered equipment

• Laptop, notebook, and palmtop computers

• PCMCIA VCC and VPP regulation/switching

• Consumer/personal electronics

• SMPS post-regulator/dc-to-dc modules

• High-efficiency linear power supplies

Typical Application

MIC5245-x.xBM5

V

IN

Enable

Shutdown

N (pin 3) may be

onnected directly

IN (pin 1).

EN

Part Number Marking Voltage Junction Temp. Range Package

MIC5245-2.5BM5 LS25 2.5V –40°C to +125°C SOT-23-5
MIC5245-2.7BM5 LS27 2.7V –40°C to +125°C SOT-23-5
MIC5245-2.8BM5 LS28 2.8V –40°C to +125°C SOT-23-5
MIC5245-2.85BM5 LS2J 2.85V –40°C to +125°C SOT-23-5
MIC5245-3.0BM5 LS30 3.0V –40°C to +125°C SOT-23-5
MIC5245-3.1BM5 LS31 3.1V –40°C to +125°C SOT-23-5
MIC5245-3.3BM5 LS33 3.3V –40°C to +125°C SOT-23-5
MIC5245-3.3BMM — 3.3V –40°C to +125°C MSOP-8

Other voltages available. Contact Micrel for details.

15
2
3

4

V

C

BYP

(optional)

OUT

C

OUT

SHUTDOWN

V

IN

V

OUT

C

ENABLE

OUT

MIC5245-3.3MM

1
2
3
4

C

BYP

(OPTIONAL)

8
7
6
5

Ultra-Low-Noise Regulator Application

Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com

June 2000 1 MIC5245

MIC5245 Micrel

Pin Configuration

GND

2

IN

13

OUTBYP

EN

IN

OUT

BYP

1
2
3
4

8-Pin MSOP (BMM)

EN

LSxx

45

MIC5245-x.xBM5

Pin Description

Pin Number Pin Number Pin Name Pin Function

Power MOS-8 SOT-23

2 1 IN Supply Input

5–8 2 GND Ground

1 3 EN Enable/Shutdown (Input): CMOS compatible input. Logic high = enable;

logic low = shutdown. Do not leave open.

4 4 BYP Reference Bypass: Connect external 0.01µF capacitor to GND to reduce

output noise. May be left open.

3 5 OUT Regulator Output

8 GND

GND

7

GND

6

GND

5

Absolute Maximum Ratings (Note 1)

Supply Input Voltage (VIN) .................................. 0V to +7V

Enable Input Voltage (VEN) ................................. 0V to +7V

Junction Temperature (TJ) ...................................... +150°C

Storage Temperature ............................... –65°C to +150°C

Lead Temperature (soldering, 5 sec.) ....................... 260°C

Operating Ratings (Note 2)

Input Voltage (VIN) ......................................... +2.7V to +6V

Enable Input Voltage (VEN) .................................. 0V to V

Junction Temperature (TJ) ....................... –40°C to +125°C

Thermal Resistance

SOT-23 (θJA) .....................................................235°C/W

MSOP-8 (θJA)......................................................80°C/W

IN

ESD, Note 3

MIC5245 2 June 2000

MIC5245 Micrel

Electrical Characteristics

VIN = V

Symbol Parameter Conditions Min Typical Max Units

V

O

∆V

LNR

∆V

LDR

VIN – V

I

Q

I

GND

PSRR Power Supply Rejection f = 120Hz, C
I

LIM

e

n

Enable Input

V

IL

V

IH

I

EN

Thermal Protection

+ 1V, VEN = V

OUT

Output Voltage Accuracy I

Line Regulation VIN = V
Load Regulation I

OUT

Dropout Voltage, Note 5 I

Quiescent Current VEN ≤ 0.4V (shutdown) 0.2 1 µA
Ground Pin Current, Note 6 I

Current Limit V
Output Voltage Noise C

Enable Input Logic-Low Voltage VIN = 2.7V to 5.5V, regulator shutdown 0.8 0.4 V
Enable Input Logic-High Voltage VIN = 2.7V to 5.5V, regulator enabled 2.0 1V
Enable Input Current VIL ≤ 0.4V 0.17 µA

Shutdown Resistance Discharge 500 Ω

Thermal Shutdown Temperature 150 °C
Thermal Shutdown Hysteresis 10 °C

= 100µA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted.

IN; IOUT

= 0mA –11%

OUT

+ 0.1V to 6V –0.3 0 0.3 %/V

OUT

= 0.1mA to 150mA, Note 4 2.0 3.0 %

OUT

= 100µA 1.5 5 mV

OUT

I

= 50mA 50 85 mV

OUT

I

= 100mA 100 150 mV

OUT

I

= 150mA 150 200 mV

OUT

= 0mA 100 150 µA

OUT

I

= 150mA 100 µA

OUT

= 10µF, C

OUT

= 0V 160 300 mA

OUT

= 10µF, C

OUT

f = 10Hz to 100kHz

= 0.01µF, 30

BYP

= 0.01µF50dB

BYP

VIH ≥ 2.0V 1.5 µA

–22%

250 mV

µV(rms)

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. Devices are ESD sensitive. Handling precautions recommended.
Note 4. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load

Note 5. Dropout Voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1V

Note 6. Ground pin current is the regulator quiescent current. The total current drawn from the supply is the sum of the load current plus the ground

range from 0.1mA to 150mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.

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 voltage is 2.7V.

pin current.

June 2000 3 MIC5245

MIC5245 Micrel

Typical Characteristics

Power Supply

100

PSRR (dB)

Rejection Ratio

10k

VIN = 4V
V

OUT

100k

= 3V

1M

I

= 100µA

OUT

C

= 1µF tant

80

OUT

60

40

20

0

1E+11E+21E+31E+41E+51E+61E+7

10

1k

100

FREQUENCY (Hz)

Power Supply

100

PSRR (dB)

Rejection Ratio

10k

VIN = 4V
V

OUT

100k

= 3V

1M

I

= 150mA

OUT

C

= 1µF tant

80

OUT

60

40

20

0

1E+11E+21E+31E+4 1E+51E+61E+7

10

1k

100

FREQUENCY (Hz)

10M

10M

Power Supply

100

80

60

40

PSRR (dB)

20

Rejection Ratio

I

= 10mA

OUT

C

= 1µF tant

OUT

0

1E+11E+21E+31E+4 1E+51E+61E+7

10

1k

100

FREQUENCY (Hz)

10k

VIN = 4V
V

OUT

100k

= 3V

1M

Power Supply

100

PSRR (dB)

Rejection Ratio

80

60

40

I

= 100µA

20

VIN = 4V
V

OUT

0

1E+11E+21E+3 1E+41E+51E+61E+7

100 1k 10k 100k 1M 10M

10

OUT

C

= 10µF cer.

OUT

= 3V

C

= 0.01µF

BYP

FREQUENCY (Hz)

10M

Power Supply

100

80

60

40

PSRR (dB)

20

Rejection Ratio

I

= 100mA

OUT

C

= 1µF tant

OUT

0

1E+11E+21E+31E+4 1E+51E+61E+7

10

1k

100

FREQUENCY (Hz)

10k

VIN = 4V
V

OUT

100k

= 3V

1M

Power Supply

100

80

60

40

PSRR (dB)

20

Rejection Ratio

VIN = 4V
V

= 3V

OUT

I

= 10mA

OUT

C

= 10µF cer.

OUT

C

= 0.01µF

0

1E+11E+21E+31E+4 1E+51E+61E+7

100 1k 10k 100k 1M 10M

10

BYP

FREQUENCY (Hz)

10M

Power Supply

100

PSRR (dB)

Rejection Ratio

VIN = 4V
V

80

60

40

20

= 3V

OUT

I

= 100mA

OUT

C

= 10µF cer.

OUT

C

= 0.01µF

0

1E+11E+21E+31E+4 1E+51E+61E+7

100 1k 10k 100k 1M 10M

10

BYP

FREQUENCY (Hz)

Power Supply Ripple Rejection

vs. Voltage Drop

80
70
60
50
40
30
20

RIPPLE REJECTION (dB)

10

0

0 200 400 600 800 1000

I

= 100mA

OUT

100mA

10mA

C
C

VOLTAGE DROP (mV)

100µA

= 10µF cer.

OUT

= 0.01µF

BYP

Power Supply

100

80

60

40

PSRR (dB)

20

NOISE (µV/√Hz)

Rejection Ratio

VIN = 4V
V

= 3V

OUT

I

= 150mA

OUT

C

= 10µF cer.

OUT

C

= 0.01

BYP

0

1E+11E+21E+31E+4 1E+51E+61E+7

100 1k 10k 100k 1M 10M

10

FREQUENCY (Hz)

Noise Performance

10

IL = 100µA

1

VIN = 4V

0.1

V

= 3V

OUT

C

= 1µF cer.

OUT

C

= 0.01µF

BYP

0.01
10 100 1k 10k 100k 1M

1E+1 1E+2 1E+3 1E+4 1E+5 1E+6

FREQUENCY (Hz)

Power Supply Ripple Rejection

vs. Voltage Drop

80
70
60
50
40
30
20

RIPPLE REJECTION (dB)

10

0

0 200 400 600 800 1000

10

1

VIN = 4V

0.1

V

NOISE (µV/√Hz)

0.01
10

1E+1 1E+2 1E+3 1E+4 1E+5 1E+6

10mA100µA

I

= 100mA

OUT

C

VOLTAGE DROP (mV)

Noise Performance

= 3V

OUT

C

= 10µF cer.

OUT

C

= 0.01µF

BYP

1k

100

FREQUENCY (Hz)

10k

150mA

= 1µF

OUT

IL = 100µA

100k

1M

MIC5245 4 June 2000