Micrel MIC5239 User Manual

General Description

MIC5239

Low Quiescent Current 500mA µCap

Features

LDO Regulator

The MIC5239 is a low quiescent current, µCap low-dropout regulator. With a maximum operating input voltage of 30V and a quiescent current of 23µA, it is ideal for supplying keep-alive power in systems with high voltage batteries.

Capable of 500mA output, the MIC5239 has a dropout voltage of only 350mV. It can provide high output current for applications such as USB.

As a µCap LDO, the MIC5239 is stable with either a ceramic or a tantalum output capacitor. It only requires a

3.3µF output capacitor for stability. The MIC5239 includes a logic compatible enable input and

an undervoltage error flag indicator. Other features of the MIC5239 include thermal shutdown, current limit, overvoltage shutdown, reverse-leakage protection, and reversebattery protection.

Available in the thermally enhanced SOIC-8, MSOP-8 and

• Ultra-low quiescent current (I

• Continuous 500mA output current

• Wide input range: 2.3V to 30V

• Low dropout voltage: 350mV @500mA

• ±1.0% initial output accuracy

• Stable with ceramic or tantalum output capacitor

• Logic compatible enable input

• Low output voltage error flag indicator

• Overcurrent protection

• Thermal shutdown

• Reverse-leakage protection

• Reverse-battery protection

• High-power SOIC-8, MSOP-8 and SOT-223 packages

Applications

= 23µA @I

= 100µA)

SOT-223, the MIC5239 comes in fixed 1.5V, 1.8V, 2.5V,

3.0V, 3.3V and 5.0V, and adjustable voltages. For other output voltages, contact Micrel.

All support documentation can be found on Micrel’s web site at: www.micrel.com.

• USB power supply

• Keep-alive supply in notebook and portable personal

computers

• Logic supply from high voltage batteries

• Automotive electronics

• Battery-powered systems

___________________________________________________________________________________________________________

Typical Application

30V

Regulator with Low IO and Low IQ

MIC5239

GND

OUT

FLG

OUT

3.0V/100µA

= 23µA

GND

= 1mA

OUT

= 10µA

OUT

914

OUT

= 100µA

MLF and MicroLeadFrame is a registered trademark of Amkor Technologies

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

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Ground Current vs. Input Voltage

408

) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

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Ordering Information

Part Number

Standard Pb-Free

MIC5239-1.5BM

MIC5239-1.5BMM MIC5239-1.5YMM 1.5V –40°C to +125°C 8-pin MSOP

MIC5239-1.5BS MIC5239-1.5YS 1.5V –40°C to +125°C SOT-223

MIC5239-1.8BM MIC5239-1.8YM 1.8V –40°C to +125°C 8-pin SOIC

MIC5239-1.8BMM MIC5239-1.8YMM 1.8V –40°C to +125°C 8-pin MSOP

MIC5239-1.8BS MIC5239-1.8YS 1.8V –40°C to +125°C SOT-223

MIC5239-2.5BM MIC5239-2.5YM 2.5V –40°C to +125°C 8-pin SOIC

MIC5239-2.5BMM MIC5239-2.5YMM 2.5V –40°C to +125°C 8-pin MSOP

MIC5239-2.5BS MIC5239-2.5YS 2.5V –40°C to +125°C SOT-223

MIC5239-3.0BM MIC5239-3.0YM 3.0V –40°C to +125°C 8-pin SOIC

MIC5239-3.0BMM MIC5239-3.0YMM 3.0V –40°C to +125°C 8-pin MSOP

MIC5239-3.0BS MIC5239-3.0YS 3.0V –40°C to +125°C SOT-223

MIC5239-3.3BM MIC5239-3.3YM 3.3V –40°C to +125°C 8-pin SOIC

MIC5239-3.3BMM MIC5239-3.3YMM 3.3V –40°C to +125°C 8-pin MSOP

MIC5239-3.3BS MIC5239-3.3YS 3.3V –40°C to +125°C SOT-223

MIC5239-5.0BM MIC5239-5.0YM 5.0V –40°C to +125°C 8-pin SOIC

MIC5239-5.0BMM MIC5239-5.0YMM 5.0V –40°C to +125°C 8-pin MSOP

MIC5239-5.0BS MIC5239-5.0YS 5.0V –40°C to +125°C SOT-223

MIC5239BM MIC5239YM ADJ –40°C to +125°C 8-pin SOIC

MIC5239BMM MIC5239YMM ADJ –40°C to +125°C 8-pin MSOP

Note:

1. Other Voltages available. Contact Micrel for details.

MIC5239-1.5YM

Voltage

1.5V

(1)

Junction Temp. Range Package

–40°C to +125°C 8-pin SOIC

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Pin Configuration

SOIC-8 (M) SOT-223 (S) SOIC-8 (M) MSOP-8(MM) MSOP-8(MM) (Fixed) (Adj)

Pin Description

Pin Number MSOP/SOIC

2 (fixed) — FLG

2 (adj) — ADJ Adjustable Feedback Input: Connect to voltage divider network.

3 1 IN Power Supply Input.

4 3 OUT Regulated Output.

1 — EN Enable (input): Logic low = shutdown; logic high = enabled.

5–8 2 GND

Pin Number

SOT-223

Pin Name Pin Function

Error FLAG (Output): Open-collector output is active low when the output is out of regulation due to insufficient input voltage or excessive load. An external pull-up resistor is required.

Ground: Pins 5, 6, 7, and 8 are internally connected in common via the leadframe.

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Absolute Maximum Ratings

(1)

Operating Ratings

(2)

Supply Voltage (VIN) ...................................... –20V to +32V

Enable Input Voltage (V Power Dissipation (P Junction Temperature (T Storage Temperature (T

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

ESD Rating

(4)

)............................ –0.3V to +32V

(3)

)

...........................Internally Limited

) ........................–40°C to +125°C

).........................–65°C to +150°C

SOT-23-3L ...............................................................2kV

MSOP-8L ..............................................................1.5kV

Supply Voltage (VIN).......................................... 2.3V to 30V

Enable Input Voltage (V Junction Temperature (T

)................................... 0V to 30V

) ........................–40°C to +125°C

Package Thermal Resistance MSOP ( SOT-223 (

)....................................................... 80°C/W

)................................................... 50°C/W

= 100µA; T

OUT

(7)

(5)

= 25°C, bold values indicate –40°C  T

–1

OUT

+1V to 30V 0.06 0.5 %

OUT

= 100µA to 500mA

OUT

= 100µA 50 mV

OUT

= 150mA

OUT

= 500mA 350 mV

OUT

VEN  2.0V, I

 2.0V, I

= 0V 850

OUT

= 100µA

OUT

= 150mA 1.3 5 mA

OUT

= 500mA 8.5 15 mA

OUT

= 30V 0.1 1 µA

(6)

15 30 mV

= 3.0V, CL = 3.3µF 160

OUT

 +125°C; unless noted.

–2

260

1 2

350

400

1200

% %

mV mV

µA µA

µVrms

Electrical Characteristics

= V

Symbol Parameter Condition Min Typ Max Units

OUT

V

+ 1V; V

OUT

Output Voltage Accuracy Variation from nominal V

OUT/VOUT

Line Regulation VIN = V

Load Regulation I

V Dropout Voltage

Ground Pin Current

GND

GND(SHDN)

Ground Pin Shutdown VEN  0.6V, V

ISC Short Circuit Current V

en Output Noise 10Hz to 100kHz, V

 2.0V; I

FLAG Output

FLG

Low Threshold % of V

High Threshold % of V

VOL FLAG Output Low Voltage VIN = V

FLAG Output Leakage VOH = 30V 0.1 µA

LEAK

94 % V

OUT

95 %

OUT

OUT(nom)

– 0.12V

, IOL = 200µA 150 mV

OUT

Enable Input

VIL Input Low Voltage regulator off 0.6 V

VIH Input High Voltage regulator on 2.0

IIN Enable Input Current

VEN = 0.6V, regulator off –1.0

–2.0

VEN = 2.0V, regulator on

= 30V, regulator on

0.15

0.5

0.01

1.0

2.0

1.0

2.0

2.5

5.0

µA µA

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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 T

allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The  x.xBMM (all versions) is 80°C/W, the MIC5239-x.xBM (all versions) is 63°C/W, and the MIC5239-x.xBS (all versions) is 50°C/W mounted on a PC board, see “Thermal Characteristics” for further details.

4. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.

5. Specification for packaged product only.

6. Regulation is measured at constant junction temperature using pulse testing with a low duty-cycle. Changes in output voltage due to heating effects are covered by the specification for thermal regulation.

7. Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1.0V differential.

(ambient temperature) is PD(max) = (TJ(max) – TA) ÷ JA. Exceeding the maximum

of the MIC5239-

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Typical Characteristics

OUT

= 3V)

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Typical Characteristics (continued)

OUT

= 3V)

Input Current

120

)Am(TNERRUCTUPNI

100

VEN = 5V

-20 -10 0 10

= 30

LOAD

SUPPLY VOLTAGE (V)

Functional Characteristics

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Functional Diagram

Block Diagram — Fixed Voltages

Block Diagram — Adjustable Voltages

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Application Information

The MIC5239 provides all of the advantages of the MIC2950: wide input voltage range, and reversedbattery protection, with the added advantages of reduced quiescent current and smaller package. Additionally, when disabled, quiescent current is reduced to 0.1µA.

Enable

A low on the enable pin disables the part, forcing the quiescent current to less than 0.1µA. Thermal shutdown and the error flag are not functional while the device is disabled. The maximum enable bias current is 2µA for a

2.0V input. An open-collector pull-up resistor tied to the input voltage should be set low enough to maintain 2V on the enable input. Figure 1 shows an open-collector output driving the enable pin through a 200k pull-up resistor tied to the input voltage.

In order to avoid output oscillations, slow transitions from low-to-high should be avoided.

200

200k

Figure 1. Remote Enable

MIC5239

GND

OUT

FLG

Input Capacitor

An input capacitor may be required when the device is not near the source power supply or when supplied by a battery. Small, surface mount ceramic capacitors can be used for bypassing. Larger values may be required if the source supply has high ripple.

Output Capacitor

The MIC5239 has been designed to minimize the effect of the output capacitor ESR on the closed loop stability. As a result, ceramic or film capacitors can be used at the output. Figure 2 displays a range of ESR values for a 10µF capacitor. Virtually any 10µF capacitor with an ESR less than 3.4 is sufficient for stability over the entire input voltage range. Stability can also be maintained throughout the specified load and line conditions with 4.7µF film or ceramic capacitors.

Figure 2. Output Capacitor ESR

Error Detection Comparator Output

The FLAG pin is an open-collector output which goes low when the output voltage drops 5% below it’s internally programmed level. It senses conditions such as excessive load (current limit), low input voltage, and over temperature conditions. Once the part is disabled via the enable input, the error flag output is not valid. Overvoltage conditions are not reflected in the error flag output. The error flag output is also not valid for input voltages less than 2.3V.

The error output has a low voltage of 400mV at a current of 200µA. In order to minimize the drain on the source used for the pull-up, a value of 200k to 1M is suggested for the error flag pull-up. This will guarantee a maximum low voltage of 0.4V for a 30V pull-up potential. An unused error flag can be left unconnected.

Input

4.75V

1.3V

VALID ERROR

NOT

VALID

Output

Voltage

Error FLAG

Output

Voltage

Figure 3. Error FLAG Output Timing

Thermal Shutdown

The MIC5239 has integrated thermal protection. This feature is only for protection purposes. The device should never be intentionally operated near this temperature as this may have detrimental effects on the life of the device. The thermal shutdown may become inactive while the enable input is transitioning from a high to a low. When disabling the device via the enable pin, transition from a high to low quickly. This will insure that the output remains disabled in the event of a thermal shutdown.

NOT VALID

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Current Limit

Figure 4 displays a method for reducing the steady state short-circuit current. The duration that the supply delivers current is set by the time required for the error flag output to discharge the 4.7µF capacitor tied to the enable pin. The off time is set by the 200k resistor as it recharges the 4.7µF capacitor, enabling the regulator. This circuit reduces the short-circuit current from 800mA to 40mA while allowing for regulator restart once the short is removed.

1N4148

SHUTDOWN

ENABLE

200k

4.7µF

MIC5239

GND

OUT

FLG

200k

ERR

OUT

Figure 4. Remote Enable with Short-Circuit

Current Foldback

Thermal Characteristics

The MIC5239 is a high input voltage device, intended to provide 500mA of continuous output current in two very small profile packages. The power MSOP-8 allows the device to dissipate about 50% more power than their standard equivalents.

Power MSOP-8 Thermal Characteristics

One of the secrets of the MIC5239’s performance is its power MSOP-8 package featuring half the thermal resistance of a standard MSOP-8 package. Lower thermal resistance means more output current or higher input voltage for a given package size.

Lower thermal resistance is achieved by joining the four ground leads with the die attach paddle to create a single piece electrical and thermal conductor. This concept has been used by MOSFET manufacturers for years, proving very reliable and cost effective for the user.

Thermal resistance consists of two main elements,  (junction-to-case thermal resistance) and  ambient resistance

thermal resistance). See Figure 5. 

from the die to the leads of the package. 

(case-to-

is the

is the resistance from the leads to the ambient air and it includes 

(case-to-sink thermal resistance) and 

(sink-to-ambient thermal resistance).

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Figure 5. Thermal Resistance

Using the power MSOP-8 reduces the  and allows the user to reduce  resistance, 

(junction-to-ambient thermal resistance)

. The total thermal

dramatically

is the limiting factor in calculating the maximum power dissipation capability of the device. Typically, the power MSOP-8 has a 

of 80°C/W, this is significantly lower

than the standard MSOP-8 which is typically 200°C/W.



is reduced because pins 5 through 8 can now be

soldered directly to a ground plane which significantly reduces the case-to-sink thermal resistance and sink to ambient thermal resistance.

Low-dropout linear regulators from Micrel are rated to a maximum junction temperature of 125°C. It is important not to exceed this maximum junction temperature during operation of the device. To prevent this maximum junction temperature from being exceeded, the appropriate ground plane heatsink must be used.

Figure 6. Copper Area vs. Power-MSOP

Power Dissipation (∆T

)

Figure 6 shows copper area versus power dissipation with each trace corresponding to a different temperature rise above ambient.

From these curves, the minimum area of copper necessary for the part to operate safely can be determined. The maximum allowable temperature rise must be calculated to determine operation along which curve.

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T = T

(max) – TA(max)

(max) = 125°C

(max) = maximum ambient operating

temperature

For example, the maximum ambient temperature is 50°C, the T is determined as follows:

T = 125°C – 50°C

T = 75°C

Using Figure 6, the minimum amount of required copper can be determined based on the required power dissipation. Power dissipation in a linear regulator is calculated as follows:

= (VIN – V

OUT

) I

+ VIN × I

OUT

GND

If we use a 3V output device and a 28V input at

Figure 8. Copper Area vs. Power-SOIC

Power Dissipation (∆TJA)

moderate output current of 25mA, then our power dissipation is as follows:

= (28V – 3V) × 25mA + 28V 250µA

= 625mW + 7mW

= 632mW

From Figure 6, the minimum amount of copper required to operate this application at a T of 75°C is 110mm

Quick Method

Determine the power dissipation requirements for the design along with the maximum ambient temperature at which the device will be operated. Refer to Figure 7, which shows safe operating curves for three different ambient temperatures: 25°C, 50°C and 85°C. From these curves, the minimum amount of copper can be determined by knowing the maximum power dissipation required. If the maximum ambient temperature is 50°C and the power dissipation is as above, 639mW, the curve in Figure 7 shows that the required area of copper is 110mm

The 

of this package is ideally 80°C/W, but it will vary

depending upon the availability of copper ground plane to which it is attached.

Figure 9. Copper Area vs. Power-SOIC

Power Dissipation (TA)

The same method of determining the heatsink area used for the power MSOP-8 can be applied directly to the power SOIC-8. The same two curves showing power dissipation versus copper area are reproduced for the power SOIC-8 and they can be applied identically.

Power SOIC-8 Thermal Characteristics

The power SOIC-8 package follows the same idea as the power MSOP-8 package, using four ground leads with the die attach paddle to create a single-piece

electrical and thermal conductor, reducing thermal resistance and increasing power dissipation capability.

Quick Method

Determine the power dissipation requirements for the design along with the maximum ambient temperature at which the device will be operated. Refer to Figure 9, which shows safe operating curves for three different ambient temperatures, 25°C, 50°C, and 85°C. From these curves, the minimum amount of copper can be determined by knowing the maximum power dissipation

Figure 7. Copper Area vs. Power-MSOP

Power Dissipation (TA)

required. If the maximum ambient temperature is 50°C, and the power dissipation is 632mW, the curve in Figure 9 shows that the required area of copper is less than 100mm

, when using the power SOIC-8.

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Adjustable Regulator Application

The MIC5239YM can be adjusted from 1.24V to 20V by using two external resistors (Figure 10). The resistors set the output voltage based on the following equation:

⎞

⎟

⎠

Figure 10. Adjustable Voltage Application

⎛

1VV

⎜

REFOUT

⎝

Where V

Feedback resistor R2 should be no larger than 300k.

REF

= 1.23V.

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Package Information

8-Pin MSOP (MM)

SOT-223 (S)

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8-Pin SOIC (M)

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

The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its

Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product

can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for 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 injury to the user. A

Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully

use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.

indemnify Micrel for any damages resulting from such use or sale.

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Micrel MIC5239 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual