MICREL MIC29312BT, MIC29310-3.3BT, MIC29310-5.0BT Datasheet

MIC29310/29312 Micrel

MIC29310/29312

3A Fast-Response LDO Regulator

General Description

The MIC29310 and MIC29312 are low cost versions of
MIC29300 family low-dropout (LDO) regulators. Manufac­tured on Micrel’s proprietary Super beta PNP™ process, the
MIC29310/2 is a 3A LDO regulator with very low-dropout
voltage (600mV over the full load) and low ground current.
Along with a total accuracy of ±2% (over temperature, line
and load regulation) these regulators feature very fast tran­sient recovery from input voltage surges and output load
current changes.

The MIC29310 is available in fixed 3.3V and 5V outputs
voltages; the MIC29312 has an adjustable output which can
be set by two external resistors to a voltage between 1.24V
to 15V. In addition, all versions are fully protected against
overcurrent faults, reversed input polarity, reversed lead
insertion, and overtemperature operation.

A TTL logic enable (EN) pin is available in the MIC29312 to
shutdown the regulator. When not used, the device can be
set to continuous operation by connecting EN to the input
(IN).

The MIC29310/2 is available in the standard 3- and 5-pin
TO-220 and TO-263 packages with an operating junction
temperature range of 0°C to +125°C.

For applications requiring even lower dropout
voltage, input voltage greater than 16V, or an
error flag, see the MIC29300/29301/29302/

29303.

Ordering Information

Part Number Voltage Junction Temp. Range Package

MIC29310-3.3BT 3.3V 0°C to +125°C TO-220-3
MIC29310-3.3BU 3.3V 0°C to +125°C TO-263-3
MIC29310-5.0BT 5.0V 0°C to +125°C TO-220-3
MIC29310-5.0BU 5.0V 0°C to +125°C TO-263-3
MIC29312BT Adj. 0°C to +125°C TO-220-5
MIC29312BU Adj. 0°C to +125°C TO-263-5

Features

• Low cost versions of MIC29300 family

• Fast transient response

• 3A current over full temperature range

• 600mV dropout voltage at full load

• Low ground current

• Accurate 1% guaranteed tolerance

• “Zero” current shutdown mode (MIC29312)

• Fixed voltage and adjustable versions

Applications

• Processor peripheral and I/O supplies

• PC add-in cards

• High-efficiency “green” computer systems

• High-efficiency linear power supplies

• High-efficiency switching supply post regulator

• Battery-powered equipment

Typical Application

MIC29312

On
Off

V

V

IN

IN OUT

GND

V

OUT

IN

* For best performance, total series resistance

(R1 + R2) should be small enough to pass
the minimum regulator load current of 10mA.

Fixed Regulator Configuration

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

EN

IN

V

OUT

Adjustable Regulator Configuration

GND

= 1.240

OUT

ADJ

R1

R2

R1*

R2*

+ 1

July 1999 1 MIC29310/29312

V

OUT

MIC29310/29312 Micrel

Pin Configuration

TAB

TAB

MIC29310-x.xBT

TO-220 (T)

MIC29312-x.xBT

TO-220-5 (T)

3 OUT
2 GND
1IN

5 ADJ
4 OUT
3 GND
2IN
1EN

TAB

MIC29310-x.xBU

TO-263 (U)

TAB

MIC29312-x.xBU

TO-263-5 (U)

3 OUT
2 GND
1IN

5 ADJ
4 OUT
3 GND
2IN
1EN

Pin Description

Pin Number Pin Number Pin Name Pin Function

MIC29310 MIC29312

1 EN Enable (Input): Active-high, logic-level enable/shutdown control.

1 2 IN Unregulated Input: +16V maximum supply.

2, TAB 3, TAB GND Ground: Ground pin and TAB are internally connected.

3 4 OUT Regulator Output

5 ADJ Ouput Voltage Adjust: 1.24V feedback from external resistive divider.

Absolute Maximum Ratings (Note 1)

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

Power Dissipation (PD) ............................ Internally Limited

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

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

ESD, Note 3

Operating Ratings (Note 2)

Input Voltage (VIN) ....................................... +2.3V to +16V

Junction Temperature (TJ) ........................... 0°C to +125°C

Package Thermal Resistance

TO-263 (θJC) .........................................................2°C/W

TO-220 (θJC) .........................................................2°C/W

TO-220 (θJA) .......................................................55°C/W

MIC29310/29312 2 July 1999

MIC29310/29312 Micrel

Electrical Characteristics

TJ = 25°C, bold values indicate 0°C ≤ TJ ≤ +125°C; unless noted
Parameter Condition Min Typ Max Units

Output Voltage 10mA ≤ IO ≤ IFL, (V
Line Regulation IO = 10mA, (V
Load Regulation VIN = V

OUT

+ 1V, 10mA ≤ I

OUT

∆VO / ∆T Output VoltageTemperature Coefficient, Note 8 20 100 ppm/°C
Dropout Voltage ∆V

= –1%, Note 5

OUT

Ground Current I

Ground Pin VIN = 0.5V less than specified V

I

GNDDO

Current at Dropout
Current Limit V

= 0V, Note 6 3.0 3.8 A

OUT

Minimum Load Current 710mA
e

, Output Noise Voltage CL = 10µF400µV

n

(10Hz to 100kHz) IL = 100mA CL = 33µF260µV

Reference (MIC29312 only)

Reference Voltage 10mA ≤ IO ≤ IFL, V
Adjust Pin Bias Current 40 80 nA

Reference Voltage Note 9 20 ppm/°C
Temperature Coefficient

Adjust Pin Bias Current 0.1 nA/°C
Temperature Coefficient

Enable Input (MIC29312 only)

Input Logic Voltage low (off) 0.8 V

high (on) 2.4 V

Enable Pin Input Current V

= V

EN

IN

V

= 0.8V – 2 µA

EN

Regulator Output Note 10 10 µA
Current in Shutdown 20 µA

+ 1V) ≤ VIN ≤ 8V, Note 4 –2 2 %

OUT

+ 1V) ≤ VIN ≤ 16V 0.06 0.5 %

≤ I

OUT

FULL LOAD

= 100mA 80 200 mV

I

O

= 750mA 220 mV

I

O

I

= 1.5A 330 mV

O

, Notes 4, 8 0.2 1 %

IO = 3A 600 1000 mV

= 750mA, VIN = V

O

I

= 1.5A 15 mA

O

+ 1V 5 20 mA

OUT

IO = 3A 60 150 mA

. I

OUT

+ 1V ≤ VIN ≤ 8V, Note 4 1.215 1.265 V

OUT

= 10mA 2 3 mA

OUT

MAX

120 nA

15 30 µA

75 µA

4 µA

RMS
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: Full Load current is defined as 3A for the MIC29310/29312. For testing, V
Note 5: Dropout voltage is defined as the input-to-output differential when the output voltage drops to 99% of its nominal value with V

Note 6: For this test, VIN is the larger of 8V or V
Note 7: 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

Note 8: Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Note 9: V
Note 10: VEN ≤ 0.8V and VIN ≤ 8V, V

to VIN.

pin current.

≤ V

REF

+ 3V.

OUT

≤ (VIN – 1V), 2.4V ≤ VIN ≤ 16V, 10mA < IL ≤ IFL, TJ ≤ T

OUT

OUT

= 0.

J(max).

is programmed to 5V.

OUT

+ 1V applied

OUT

July 1999 3 MIC29310/29312

MIC29310/29312 Micrel

Block Diagram

IN

*EN

On/Off

Thermal

Shut­down

Bias

Reference

16V

* MIC29312 only.MIC29310/29312

O.V.
I

LIMIT

Feed-

back

OUT

ADJ*

GND

MIC29310/29312 4 July 1999