MICREL MIC2954-03BZ, MIC2954-07BM, MIC2954-08BM, MIC2954-03BT, MIC2954-02BS Datasheet

MIC2954 Micrel

SHUTDOWN

ENABLE

MIC2954

IN OUT

GND

10µF

V

IN

V

OUT

1.2V to 30V

SHDN

FB

R1

100pF

R2

ERR

100k V

ERR

2, 6 = OPEN

1

3

8

5
7

4

V

REF

VV1

R1

R2

OUT

REF

=+











SHUTDOWN

ENABLE

MIC2954-07/-08

IN OUT

GND

V

IN

V

OUT

≈ VIN*

SHDN

FB

ERR

* MINIMUM INPUT-TO-OUTPUT

VOLTAGE RANGES FROM
40mV TO 400mV DEPENDING
UPON LOAD CURRENT

1

3

8

5
7

4

MIC2954

250mA Low-Dropout Regulator

General Description

The MIC2954 is a “bulletproof” efficient voltage regulator with
very low dropout voltage (typically 40mV at light loads and
375mV at 250mA), and low quiescent current (120µA typi­cal). The quiescent current of the MIC2954 increases only
slightly in dropout, thus prolonging battery life. Key MIC2954
features include protection against reversed battery, fold­back current limiting, and automotive load dump protection
(60V positive transient).

The MIC2954-07/08BM is an adjustable version that includes
an error flag output that warns of a low output voltage, which
is often due to failing batteries on the input. This may also be
used as a power-on reset. A logic-compatible shutdown input
is provided which enables the regulator to be switched on and
off. This part may be pin-strapped for 5V output, or pro­grammed from 1.24V to 29V with the use of two external
resistors.

The MIC2954 is available in two voltage tolerances, ±0.5%
maximum and ±1% maximum. Both are guaranteed for
junction temperatures from –40°C to +125°C.

The MIC2954 has a very low output voltage temperature
coefficient and extremely good load and line regulation
(0.04% typical).

Features

• High-accuracy 5V, guaranteed 250mA output

• Low quiescent current

• Low dropout voltage

• Extremely tight load and line regulation

• Very low temperature coefficient

• Current and thermal limiting

• Input can withstand –20V reverse battery and
+60V positive transients

• Error flag warns of low output voltage

• Logic-controlled electronic shutdown

• Output programmable from 1.24V to 29V
(MIC2954-07/08)

• Available in TO-220, TO-92, and surface-mount
SOT-223 and SOP-8 packages

Applications

• Battery powered equipment

• Cellular telephones

• Laptop, notebook, and palmtop computers

• PCMCIA VCC and V

• Bar code scanners

• Automotive electronics

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

• Voltage reference

• High-efficiency linear power supplies

regulation/switching

PP

T ypical Applications

SHUTDOWN

ENABLE

5V or 3V Selectable Regulator with Shutdown

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

August 1999 1 MIC2954

IN

IN OUT

MIC2954

V

GND

5V Fixed Regulator

V

IN

MIC2954-07/-08

+7V

8

IN OUT

3

SHDN

GND

5V

3.3V

1
5

ERR

7

FB

220k

4

470k

Q1 ON = 3.3V

Q1 OFF = 5.0V

V

OUT

2.2µF

100pF

180k

1%

Q1
2N2222

1%

300k
1%

V

OUT

5V or 3.3V

3.3µF

Adjustable Regulator

Wide Input-Voltage-Range Current Limiter

MIC2954 Micrel

IN OUTGND

132

TAB

GND

Ordering Information

Part Number Accuracy Junc. Temp. Range Package

MIC2954-02BT 0.5% –40°C to +125°C TO-220
MIC2954-03BT 1.0% –40°C to +125°C TO-220
MIC2954-02BS 0.5% –40°C to +125°C SOT-223
MIC2954-03BS 1.0% –40°C to +125°C SOT-223
MIC2954-02BZ 0.5% –40°C to +125°C TO-92
MIC2954-03BZ 1.0% –40°C to +125°C TO-92
MIC2954-07BM 0.5% –40°C to +125°C SOP-8
MIC2954-08BM 1.0% –40°C to +125°C SOP-8

Pin Configuration

MIC2954

OUT
SNS

1
2

IN

8

FB

7

SHDN

GND

3
4

TAP

6
5

ERR

SOP-8 (M)

321

TAB

OUT IN

GND

TO-92 (Z)

Pin Description

Pin No. Pin No. Pin No. Pin No. Pin Name Pin Function

SOT-223 SOP-8 TO-220 TO-92

1 8 1 1 IN Supply Input

2, TAB 4 2 2 GND Ground

3 1 3 3 OUT Regulator Output

2 SNS Sense (Input): Output-sense-voltage end of internal resistive

divider. Connect to OUT (V
also see TAP. Not used in adjustable configuration.

3 SHDN Shutdown (Input): Active-low input enables regulator.

(Low = enable; high = shutdown.)

5 ERR Error Flag (Output): Open collector (active-low) output. Active

state indicates an output (V
(Low = error, floating = normal.)

6 TAP Divider Tap (Output): Resistive voltage divider tap. With 5V

7 FB Feedback (Input): Error amplifier input. Compared to internal

applied to SNS, V
FB for 5V operation. Not used in adjustable configuration.

1.23V reference. Connect to external voltage divider for
adjustable operation or internal voltage divider (TAP) for 5V
operation (see SNS, TAP).

SOT-223 (S)

TO-220 (T)

= 5V) for fixed 5V operation;

OUT

) undervoltage condition.

OUT

is approximately 1.23V. Connect to

TAP

3 OUT
2 GND
1IN

MIC2954 2 August 1999

MIC2954 Micrel

Absolute Maximum Ratings (Note 1)

Input Voltage (VIN) ........................................ –20V to +60V

Feedback Voltage (VFB), Note 14,15........... –1.5V to +26V

Shutdown Input Voltage (V
Error Output Voltage (V

ERR

) ................. –0.3V to +30V

SHDN

) ........................ –0.3V to +30V

Operating Ratings (Note 2)

Input Voltage (VIN) .......................................+2.0V to +30V

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

Package Thermal Temperature (θ

)................ Note 5

JC, θJA

Power Dissipation (PD), Note 4 ...............Internally Limited

Storage Temperature (TS) .......................–65°C to +150°C

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

ESD, Note 3

Electrical Characteristics

MIC2954-07/08: VFB = V

bold values indicate –40°C ≤ TJ ≤ +125°C; Note 8; unless noted.
Symbol Parameter Conditions Min Typ Max Units

V

OUT

Output Voltage MIC2954-02/-07 (±0.5%) 4.975 5.000 5.025 V

TAP

; V

SNS

= V

OUT

; V

≤ 0.6V. All versions: VIN = 6V; IL = 1mA; CL = 2.2µF; TJ = 25°C,

SHDN

4.940 5.060 V
MIC2954-02/-07 (±0.5%), 1mA ≤ IL ≤ 250mA 4.930 5.000 5.070 V
MIC2954-03/-08 (±1%) 4.950 5.000 5.050 V

4.900 5.100 V
MIC2954-03/-08 (±1%), 1mA ≤ IL ≤ 250mA 4.880 5.000 5.120 V

∆V

/∆T Output Voltage MIC2954-02/-07 (±0.5%) 20 100 ppm/°C

OUT

∆V

OUT/VOUT

∆V

OUT/VOUT

V

– V

IN

I

GND

I

GND(DO)

OUT

Temperature Coefficient, Note 6

MIC2954-03/-08 (±1%) 20 150 ppm/°C

Line Regulation, Note 7 MIC2954-02/-07 (±0.5%), VIN = 6V to 26V 0.03 0.10 %/V

MIC2954-03/-08 (±1%), V

= 6V to 26V 0.03 0.20 %/V

IN

Load Regulation, Note 8 MIC2954-02/-07 (±0.5%), IL = 1 to 250mA, 0.04 0.16 %/V

MIC2954-03/-08 (±1%), I

= 1 to 250mA, 0.04 0.20 %/V

L

Dropout Voltage, Note 9 IL = 1mA 60 100 mV

I

= 50mA 220 250 mV

L

= 100mA 250 300 mV

I

L

= 250mA 375 450 mV

I

L

Ground Pin Current, Note 10 IL = 1mA 140 200 µA

I

= 50mA 0.5 1 mA

L

I

= 100mA 1.7 2.5 mA

L

I

= 250mA 5 9 mA

L

Ground Pin Current at Dropout, VIN = 4.5V 180 300 µA

Note 10

0.20 %/V

0.40 %/V

0.20 %/V

0.30 %/V

150 mV

420 mV

450 mV

600 mV

300 µA

2 mA

3.5 mA

12 mA

I

LIMIT

Current Limit, Note 11 V

= 0V 750 mA

OUT

800 mA

August 1999 3 MIC2954

MIC2954 Micrel

Symbol Parameter Conditions Min Typ Max Units

∆V

/∆P

OUT

e

n

Error Comparator

Shutdown Input

Thermal Regulation, Note 12 0.05 0.2 %/W

D

Output Noise Voltage IL = 100mA, CL = 2.2µF 400 µV(rms)
(10Hz to 100kHz)

IL = 100mA, CL = 33µF 260 µV(rms)

Reference Voltage MIC2954-02/-07 (±0.5%) 1.220 1.235 1.250 V

1.200 1.260 V

MIC2954-03/-08 (±1%) 1.210 1.235 1.260 V

1.200 1.270 V

Reference Voltage MIC2954-02/-07 (±0.5%), Note 13 1.190 1.270 V

MIC2954-03/-08 (±1%), Note 13 1.185 1.285 V

Feedback Pin Bias Current 20 40 nA

60 nA

Reference Voltage MIC2954-02/-07 (±0.5%) 20 ppm/°C
Temperature Coefficient, Note 12

MIC2954-03/-08 (±1%) 50 ppm/°C

Feedback Pin Bias Current 0.1 40 nA/°C
Temperature Coefficient

Output Leakage Current V

Output Low Voltage V

= 30V 0.01 1.00 µA

OH

= 4.5V, IOL = 400µA 150 250 mV

IN

2.00 µA

400 mV

Upper Threshold Voltage Note 14 60 40 mV

25 mV

Lower Threshold Voltage Note 14 75 95 mV

140 mV

Hysteresis Note 14 15 mV

Input Logic Voltage low (on) 1.3 0.7 V

high (off) 2.0 V

Shutdown Pin Input Current V

= 2.4V 30 50 µA

SHDN

100 µA

V

= 30V 450 600 µA

SHDN

750 µA

Regular Output Current in Note 15 310µA
Shutdown 20 µA

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. P
Note 5. Thermal resistance (θJC) of the TO-220 package is 2.5°C/W, and 15°C/W for the SOT-223. Thermal resistance (θJC) of the TO-92 package is

Note 6. Output voltage temperature coefficient is defined as the worst case voltage change divide by the total temperature range.
Note 7. Line regulation for the MIC2954 is tested at 125°C for IL = 1mA. For IL = 100µA and TJ = 125°C, line regulation is guaranteed by design to

Note 8. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Changes in output voltage due to heating effects

Note 9. Dropout Voltage is defined as the input to output differential at which the output voltage drops 100 mV below its nominal value measured at 1V

Note 10. Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the load current plus the ground

= (T

D(max)

180°C/W with 0.4" leads and 160°C/W with 0.25" leads. Thermal resistance (θJA) of the SOP-8 is 160°C/W mounted on a printed circuit board
(See “Application Information: Thermal Calculation”).

0.2%. See “Typical Characteristics” for line regulation versus temperature and load current.

are covered by the thermal regulation specification.

differential. At very low values of programmed output voltage, the minimum input supply voltage of 2 V (2.3V over temperature) must be taken
into account.

pin current.

– TA) ÷ θJC. Exceeding T

J(max)

will cause thermal shutdown.

J(max)

MIC2954 4 August 1999