MIC5318YD5TR - Micrel, Inc.

MIC5318

High Performance 300mA

µCap ULDO™

ULDO is a trademark of Micrel, Inc.

MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

General Description

The MIC5318 is a high performance, single output

ultra low drop-out (ULDO™) regulator, offering low

total output noise in an ultra-small Thin MLF®

package. The MIC5318 is capable of sourcing 300mA

output current and offers high PSRR and low output

noise, making it an ideal solution for RF applications.

Ideal for battery operated applications, the MIC5318

offers 2% initial accuracy, extremely low dropout

voltage (110mV @ 300mA), and low ground current

(typically 85µA total). The MIC5318 can also be put

into a zero-off-mode current state, drawing no current

when disabled.

The MIC5318 is available in the 1.6mm x 1.6mm Thin

MLF® package, occupying only 2.56mm2 of PCB area,

fully a 36% reduction in board area when compared to

SC-70 and 2mm x 2mm MLF® packages.

The MIC5318 has an operating junction temperature

range of –40°C to +125°C and is available in fixed and

adjustable output voltages in lead-free (RoHS

compliant) Thin MLF® and Thin SOT23-5 packages.

Data sheets and support documentation can be found

on Micrel’s web site at: www.micrel.com.

Features

• Ultra low dropout voltage 110mV @ 300mA

• Input voltage range: 2.3V to 6.0V

• 300mA guaranteed output current

• Stable with ceramic output capacitors

• Ultra low output noise – 30µVrms

• Low quiescent current – 85µA total

• High PSRR > 70dB@1kHz

• Less than 35µs turn-on time

• High output accuracy

– ± 2% initial accuracy

– ± 3% over temperature

• Thermal shutdown and current limit protection

• Tiny 6-pin 1.6mm x 1.6mm Thin MLF® package

• Thin SOT23-5 package

Applications

• Mobile phones

• PDAs

• GPS receivers

• Portable electronics

• Digital still and video cameras

Typical Application

VOUTVIN

GND

1µF

MIC5318-x.xYMT

BYP

0.01µF

Portable Application

September 2010 M9999-092810-B

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Functional Diagram

VIN

BYP

VOUT

GND

Current

Limit

LDO

Quick-

Start

VREF

Thermal

Shutdown

Error

Amp

MIC5318 Block Diagram – Fixed

VIN

BYP

VOUT

GND

Current

Limit

LDO

Quick-

Start

VREF

Thermal

Shutdown

Error

Amp

ADJ

MIC5318 Block Diagram – Adjustable

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Ordering Information

Part Number Marking Code Output Voltage Temperature Range Package

MIC5318-1.5YMT 15D 1.5V –40°C to +125°C 6-Pin 1.6 x 1.6 Thin MLF®

MIC5318-1.8YMT 18D 1.8V –40°C to +125°C 6-Pin 1.6 x 1.6 Thin MLF®

MIC5318-2.5YMT 25D 2.5V –40°C to +125°C 6-Pin 1.6 x 1.6 Thin MLF®

MIC5318-2.8YMT 28D 2.8V –40°C to +125°C 6-Pin 1.6 x 1.6 Thin MLF®

MIC5318-3.3YMT 33D 3.3V –40°C to +125°C 6-Pin 1.6 x 1.6 Thin MLF®

MIC5318YMT DAA ADJ –40°C to +125°C 6-Pin 1.6 x 1.6 Thin MLF®

MIC5318-1.5YD5 QD15 1.5V –40°C to +125°C 5-Pin Thin SOT23

MIC5318-1.8YD5 QD18 1.8V –40°C to +125°C 5-Pin Thin SOT23

MIC5318-2.5YD5 QD25 2.5V –40°C to +125°C 5-Pin Thin SOT23

MIC5318-2.8YD5 QD28 2.8V –40°C to +125°C 5-Pin Thin SOT23

MIC5318-3.3YD5 QD33 3.3V –40°C to +125°C 5-Pin Thin SOT23

MIC5318YD5 QDAA ADJ –40°C to +125°C 5-Pin Thin SOT23

Note:

1. For availability on other voltages, please contact Micrel for details.

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Pin Configuration

1EN

GND

6 BYP

OUT

1EN

GND

6 BYP

ADJ

OUT

6-Pin 1.6mm x 1.6mm Thin MLF® (MT)

Fixed (Top View)

6-Pin 1.6mm x 1.6mm Thin MLF® (MT)

Adjustable (Top View)

EN GND

BYP OUT

EN GND

ADJ OUT

5-Pin Thin SOT23 (D5)

Fixed (Top View)

5-Pin Thin SOT23 (D5)

Adjustable (Top View)

Pin Description

Pin No.

Thin

MLF-6

Fixed

Pin No.

Thin MLF-6

Adj.

Pin No.

Thin SOT23-5

Fixed

Pin No.

Thin SOT23-5

Adj.

Pin Name

Pin Function

1 1 3 3 EN

Enable Input. Active High. High = on, low = off.

Do not leave floating.

2 2 2 2 GND Ground

3 3 1 1 IN Supply Input.

4 4 5 5 OUT Output Voltage.

5 – – – NC No connection.

– 5 – 4 ADJ

Adjust Input. Connect to external resistor voltage

divider network.

6 6 4 – BYP

Reference Bypass: Connect external 0.01μF to

GND for reduced Output Noise. May be left open.

Exposed Heatsink Pad connected to ground

internally.

HS Pad HS Pad – – E PAD

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Absolute Maximum Ratings(1)

Supply Voltage (VIN) ..................................0V to +6.5V

Enable Input Voltage (VEN)........................0V to +6.5V

Power Dissipation, Internally Limited(3)

Lead Temperature (soldering, 3sec)..................260°C

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

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

ESD Rating(4)

Operating Ratings(2)

Supply Voltage (VIN).............................. +2.3V to +6.0V

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

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

Junction Thermal Resistance

Thin MLF-6 (θJA)...................................... 100°C/W

TSOT-23-5 (θJA) ...................................... 235°C/W

Electrical Characteristics(5)

VIN = VOUT + 1.0V; COUT = 1.0µF; IOUT = 100µA; TJ = 25°C, bold values indicate –40°C to +125°C, unless noted.

Parameter Conditions Min Typ Max Units

Variation from nominal VOUT −2.0 +2.0 %

Output Voltage Accuracy

Variation from nominal VOUT; –40°C to +125°C −3.0 +3.0

Line Regulation VIN = VOUT + 1V to 6.0V; IOUT = 100µA 0.02 0.6 %/V

Load Regulation, Note 6 IOUT = 100µA to 300mA 0.2 2.0 %

Dropout Voltage, Note 7

IOUT = 50mA; VOUT ≥ 2.8V

IOUT = 150mA; VOUT ≥ 2.8V

IOUT = 300mA; VOUT ≥ 2.8V

110

100

200

Ground Pin Current, Note 8 IOUT = 0 to 300mA 85 150 µA

Ground Pin Current in

Shutdown VEN ≤ 0.2V 0.01 1 µA

Ripple Rejection f = up to 1kHz; COUT = 1.0µF; CBYP = 0.1µF

f = 1kHz – 20kHz; COUT = 1.0µF; CBYP = 0.1µF 75

55 dB

Current Limit VOUT = 0V 340 500 900 mA

Output Voltage Noise COUT = 1.0µF; CBYP = 0.1µF; 10Hz to 100kHz 30 µVRMS

Enable Input

Logic Low 0.2

Enable Input Voltage Logic High 1.1 V

VIL ≤ 0.2V 0.01 1

Enable Input Current VIH ≥ 1.0V 0.01 1 µA

Turn-On Time

Turn-On Time COUT = 1.0µF; CBYP = 0.1µF; IOUT = 150mA 30 100 µs

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 of any TA (ambient temperature) is PD(max) = (TJ(max) – TA) / θJA. Exceeding the maximum allowable

power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown.

4. Devices are ESD sensitive. Handling precautions recommended. Human body model.

5. Specification for packaged product only.

6. Regulation is measured at constant junction temperature using low duty cycle pulse testing, changes in output voltage due to heating effects

are covered by the thermal regulation specification.

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

differential. For outputs below 2.3V, dropout voltage is the input-to-output differential with the minimum input voltage 2.3V.

8. Ground pin current is the regulation quiescent current. The total current drawn from the supply is the sum of the load current plus the ground

pin current.

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Typical Characteristics

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

Power Supply

Rejection Ratio

FREQUENCY (kHz)

10.1 100 1,000

1.5

1.6

1.7

1.9

2.1

2.0

Output Voltage

vs. Temperature

TEMPERATURE (°C)

VIN = VOUT + 1V

VOUT = 1.8V

COUT = 1µF

IOUT = 100µA

1.8

0.5

1.0

1.5

2.0

2.5

3.0

0 1234567

SUPPLY VOLTAGE (V)

Output Voltage

vs. Supply Voltage

VOUT = 2.8V

COUT = 1µF

300mA

100µA

300mA 150mA

50mA

VIN = VOUT + 1V

VOUT = 2.8V

COUT = 1µF

CBYP = 0.1µF

2.70

2.75

2.80

2.85

05 0 100 150 200 250 300

OUTPUT CURRENT (mA)

2.90

Output Voltage

vs. Output Current

VIN = VOUT + 1V

VOUT = 2.8V

COUT = 1µF

110

120

130

140

Dropout Voltage

TEMPERATURE (°C)

vs. Temperature

COUT = 1µF

300mA

150mA

50mA

100

110

120

05 0 100 150 200 250 300

OUTPUT CURRENT (mA)

Dropout Voltage

vs. Output Current

COUT = 1µF

VOUT = 2.8V

100

Ground Pin Current

vs. Temperature

TEMPERATURE (°C)

300mA

100µA

VIN = VOUT + 1V

VOUT = 1.8V

COUT = 1µF

100

110

05 0 100 150 200 250 300

OUTPUT CURRENT (mA)

Ground Pin Current

vs. Output Current

VIN = VOUT + 1V

VOUT = 2.8V

COUT = 1µF

100

110

2 2.5 3 3.5 4 4.5 5 5.5 6 6.5

INPUT VOLTAGE (V)

Ground Pin Current

vs. Input Voltage

100µA 300mA

400

420

440

460

480

500

520

540

560

580

600

2 2.5 3 3.5 4 4.5 5 5.5 6

INPUT VOLTAGE (V)

Current Limit

vs. Input Voltage

0.001

0.01

0.1

Output Noise

Spectral Density

FREQUENCY (kHz)

10.01 100 10,0000.1 1,000

VIN = 4V

VOUT = 2.8V

COUT = 1µF

CBYP = 0.1µF

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Functional Characteristics

Enable Turn-On

Enable

(0.5V/div)

Output Voltag e

(1V/div)

Time (10µs/div )

VIN = VOUT + 1V

VOUT = 2.8V

COUT = 1µF

CBYP = 0.1µF

Line Transient

Input Voltag e

(2V/div)

Output Voltag e

(50mV/div)

Time (40µs/div )

VOUT = 1.8V

COUT = 1µF

CBYP = 0.1µF

IOUT = 10mA

Load Transient

Output Voltage

(50mVV/div)

Output Current

(100mA/div)

Time (40µs/div )

VIN = VOUT + 1V

VOUT = 2.8V

COUT = 1µF

300mA

10mA

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Application Information

Enable/Shutdown

The MIC5318 comes with an active-high enable pin

that allows the regulator to be disabled. Forcing the

enable pin low disables the regulator and sends it into

a “zero” off-mode-current state. In this state, current

consumed by the regulator goes nearly to zero.

Forcing the enable pin high enables the output

voltage. The active-high enable pin uses CMOS

technology and the enable pin cannot be left floating;

a floating enable pin may cause an indeterminate

state on the output.

Input Capacitor

The MIC5318 is a high-performance, high bandwidth

device. Therefore, it requires a well-bypassed input

supply for optimal performance. A 1µF capacitor

is required from the input to ground to provide

stability. Low-ESR ceramic capacitors provide optimal

performance at a minimum of space. Additional high-

frequency capacitors, such as small-valued NPO

dielectric-type capacitors, help filter out high-

frequency noise and are good practice in any RF-

based circuit.

Output Capacitor

The MIC5318 requires an output capacitor of 1µF or

greater to maintain stability. The design is optimized

for use with low-ESR ceramic chip capacitors. High

ESR capacitors may cause high frequency oscillation.

The output capacitor can be increased, but

performance has been optimized for a 1µF ceramic

output capacitor and does not improve significantly

with larger capacitance.

X7R/X5R dielectric-type ceramic capacitors are

recommended because of their temperature perform-

ance. X7R-type capacitors change capacitance by

15% over their operating temperature range and are

the most stable type of ceramic capacitors. Z5U and

Y5V dielectric capacitors change value by as much as

50% and 60%, respectively, over their operating

temperature ranges. To use a ceramic chip capacitor

with Y5V dielectric, the value must be much higher

than an X7R ceramic capacitor to ensure the same

minimum capacitance over the equivalent operating

temperature range.

Bypass Capacitor

A capacitor can be placed from the noise bypass pin

to ground to reduce output voltage noise. The

capacitor bypasses the internal reference. A 0.1μF

capacitor is recommended for applications that require

low-noise outputs. The bypass capacitor can be

increased, further reducing noise and improving

PSRR. Turn-on time increases slightly with respect to

bypass capacitance. A unique, quick-start circuit

allows the MIC5318 to drive a large capacitor on the

bypass pin without significantly slowing turn-on time.

Refer to the Typical Characteristics subsection for

performance with different bypass capacitors.

No-Load Stability

Unlike many other voltage regulators, the MIC5318

will remain stable and in regulation with no load. This

is especially crucial for CMOS RAM keep-alive

applications.

Adjustable Regulator Application

Adjustable regulators use the ratio of two resistors to

multiply the reference voltage to produce the desired

output voltage. The MIC5318 can be adjusted from

1.25V to 5.5V by using two external resistors (Figure

1). The resistors set the output voltage based on the

following equation:

VOUT = ⎟

⎠

⎞

⎜

⎝

⎛+R2

1VREF

VREF = 1.25V

MIC5318YMT

VOUTVIN

ADJEN

GND

IN VOUT

1µF

Figure 1. Adjustable Voltage Output

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Substituting PD for PD(max) and solving for the ambient

operating temperature will give the maximum

operating conditions for the regulator circuit. The

junction-to-ambient thermal resistance for the

minimum footprint is 100°C/W.

Thermal Considerations

The MIC5318 is designed to provide 300mA of

continuous current. Maximum ambient operating

temperature can be calculated based on the output

current and the voltage drop across the part. Given

that the input voltage is 3.3V, the output voltage is

2.8V and the output current = 300mA.

The maximum power dissipation must not be

exceeded for proper operation.

For example, when operating the MIC5318-2.8YMT at

an input voltage of 3.3V and 300mA load with a

minimum footprint layout, the maximum ambient

operating temperature TA can be determined as

follows:

The actual power dissipation of the regulator circuit

can be determined using the equation:

PD = (VIN – VOUT) IOUT + VIN IGND

Because this device is CMOS and the ground current

is typically <100µA over the load range, the power

dissipation contributed by the ground current is < 1%

and can be ignored for this calculation:

0.15W = (125°C – TA)/(100°C/W)

A = 110°C

Therefore, a 2.8V application with 300mA of output

current can accept an ambient operating temperature

of 110°C in a 1.6mm x 1.6mm Thin MLF® 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. This informa-

tion can be found on Micrel's website at:

PD = (3.3V – 2.8V) × 300mA

PD = 0.15W

To determine the maximum ambient operating

temperature of the package, use the junction-to-

ambient thermal resistance of the device and the

following basic equation: http://www.micrel.com/_PDF/other/LDOBk_ds.pdf

PD(MAX) =

TJ(MAX) - TA

⎝

⎛

TJ(max) = 125°C, the maximum junction temperature of

the die θJA thermal resistance = 100°C/W.

The table below shows junction-to-ambient thermal

resistance for the MIC5318 in the 6-pin 1.6mm x

1.6mm Thin MLF® package.

Package θJA Recommended

Minimum Footprint

6-Pin 1.6x1.6 Thin MLF® 100°C/W

Thermal Resistance

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Package Information

6-Pin 1.6mm x 1.6mm Thin MLF® (MT)

5-Pin TSOT-23 (D5)

Micrel, Inc. MIC5318

September 2010 11 M9999-092810-B

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

Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This

information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,

specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any

intellectual property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel

assumes no liability whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including

liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual

property right

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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

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