MICREL MIC29311-5.1BT, MIC29311-5.1BU Datasheet

MIC29311 Micrel

MIC29311

3A Fast-Response LDO Regulator for USB

Preliminary Information

General Description

The MIC29311 is a 3A, fast response, low-dropout (LDO)
voltage regulator. Using Micrel’s proprietary Super βeta
PNP™ process, the MIC29311 offers exceptional dropout
(600mV at 3A) and low ground current (60mA at 3A). Fast
transient response allows it to recover quickly from large load
changes while maintaining a steady output. The device can
be sent into a “zero-current” off mode when the TTL compat­ible enable is brought low.

Designed specifically for Universal Serial Bus (USB) applica­tions, the MIC29311 works with USB power switches to
provide an economical solution for self-powered hubs. The

5.1V output voltage is optimized to work with lower-cost high
on-resistance USB power switches (300mΩ) to provide a
minimum of 4.75V at 500mA to downstream ports. Used with
MIC2527 quad USB power switches, the MIC29311 can
power up to 6 downstream ports.

Features of the MIC29311 include thermal shutdown, current
limit, reversed-battery and reversed-lead insertion protec­tion. An overvoltage clamp is available to maintain a safe
output when the input voltage exceeds 8V. An error flag is
also available to indicate of the output falls out of regulation,
or when an overcurrent condition occurs.

The MIC29311 is available in a 5-pin TO-220 or TO-263
package with a fixed 5.1V output voltage.

For other high current, low-dropout voltage regulators, please
see the MIC29150/300/500/750 and the MIC29310,
MIC29510, MIC29710.

Features

• Fast transient response

• 3A output current over full temperature range

• 600mV dropout voltage at full load

• Low ground current

• 3% total accuracy

• “Zero” off-mode current

• Thermal Shutdown

• Current Limiting

• Reversed battery protection

• Fixed 5.1V Output

Applications

• Self-powered USB hubs

• USB power switching

• High-efficiency linear power supplies

• High-efficiency switching supply post-regulator

Typical Application

MIC29311-5.1

10k

LDO Regulator

IN OUT

FLAGEN

GND

33µF

33µF

33µF

33µF

AC

Line

100mA

V

BUS

D+
D–
GND

Upstream
USB Port

Bold lines indicate

0.1" wide, 1-oz. copper
high-current traces.

6.3Vac
3A

max.

MIC5207-3.3

LDO Regulator

IN OUT

GND

4.7
µF

10k

47µF

3.3V USB Controller

V+

1.0

OVERCURRENT

µF

D+
D–

GND

5.8V @ 3A 5.1V

ON/OFF

Simple USB Stand-Alone 6-Port Self-Powered Hub

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

December 1998 1 MIC29311

Ferrite

Bead

0.01µF

0.01µF

0.01µF

V

BUS

D+

D–

GND

V

BUS

D+

D–

GND

V

BUS

D+

D–

GND

Downstream

USB

Port 1

4.75V min

500mA max.

Downstream

USB

Port 2

4.75V min

500mA max.

Downstream

USB

Port 6

4.75V min

500mA max.

MIC29311 Micrel

Ordering Information

Part Number Voltage Temperature Range Package

MIC29311-5.1BT 5.1V 0°C to +125°C TO-220-5
MIC29311-5.1BU 5.1V 0°C to +125°C TO-263-5

Pin Configuration

5 ERR
4 OUT

TAB

3 GND
2IN
1EN

TO-220-5 (T)

Pin Description

Pin Number Pin Name Pin Function

1 EN Enable (Input): Logic-level high enable/logic-level low shutdown control.
2 IN Unregulated Input: +16V maximum supply.

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

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

TAB

TO-263-5 (U)

overcurrent or undervoltage output conditions.

5 ERR
4 OUT
3 GND
2IN
1EN

MIC29311 2 December 1998

MIC29311 Micrel

Absolute Maximum Ratings (Note 1)

Input Voltage (VIN) ........................................ –20V to +12V

Enable Voltage (VEN) .................................... –20V to +12V

Error Output Voltage (V

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

ESD Rating, Note 3

) ............................. 0V to +12V

ERR

Operating Ratings (Note 2)

Input Voltage (VIN) ........................................................+8V

Maximum Power Dissipation (P

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

Package Thermal Resistance

TO-220-5 (θJA) ....................................................55°C/W

)..................... Note 4

D(max)

TO-220-5 (θJC) ......................................................2°C/W

TO-263-5 (θJC) ......................................................2°C/W

Electrical Characteristics

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

Output Tolerange 10mA ≤ I
Line Regulation I

= 10mA, (V

OUT

Load Regulation VIN = V
Output Voltage Temperature Note 5 20 100 ppm/°C

Coefficient
Dropout Voltage, Note 6 I

= 100mA 80 200 mV

OUT

I

= 750mA 220 mV

OUT

I

= 1.5A 330 mV

OUT

I

= 3A 600 1000 mV

OUT

Ground Current, Note 7 VIN = 6.1V, I

VIN = 6.1V, I

VIN = 6.1V, I
Dropout Ground Current VIN = 4.6V, I
Current Limit VIN = 3V, V
Minimum Load Current 710mA
Output Noise Voltage C

C

LOAD
LOAD

Error Flag Output

Output Leakage Current V

Output Low Voltage V

= 6.1V, V

IN

= 4.1V, I

IN

< 3A, (V

OUT

OUT

+ 1V, 10mA ≤ I

OUT

= 750mA 5 20 mA

OUT

= 1.5A 15 mA

OUT

= 3A 60 150 mA

OUT

= 10mA 2 3 mA

OUT

= 0V 3.0 3.8 A

OUT

+ 1V) ≤ VIN ≤ 8V –3 +3 %

OUT

+ 1V) ≤ VIN ≤ 8V 0.06 0.5 %

3A 0.2 1 %

OUT

= 10µF 400
= 33µF 260

= 8V 0.1 1 µA

ERR

= 250µA 220 300 mV

ERR

µV(rms)
µV(rms)

2 µA

400 mV

December 1998 3 MIC29311

MIC29311 Micrel

Parameter Condition Min Typ Max Units
Enable Input

Logic Low Voltage regulator shutdown 0.8 V
Logic High Voltage regulator enabled 2.4 V
Enable Input Current V

= V

EN

IN

= 0.8V 2 µA

V

EN

Regulator Output Current VIN = ≤8V, VEN ≤ 0.8V (shutdown), V

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. Output voltage temperature coefficient is defined as the ∆V
Note 6. VDO = VIN – V
Note 7. I
Note 8. VEN ≤ 0.8V and VIN ≤ 8V, V

= (T

D(max)

is the quiescent current. IIN = I

GND

– TA) ÷ θJA, where θJA depends upon the printed curcuit board layout. See “Applications Information.”

J(max)

when V

OUT

decreases to 99% of its nominal output voltage with VIN = V

OUT

OUT

= 0.

GND

+ I

OUT

.

OUT(worst case)

= 0V, Note 8 10 20 µA

OUT

÷ (T

J(max)

– T

J(min)

) where T

+ 1V.

OUT

is +125°C and T

J(max)

15 30 µA

75 µA

4 µA

is 0°C.

J(min)

MIC29311 4 December 1998