MICREL MIC5239

MIC5239
Low Quiescent Current 500mA µCap
LDO Regulator
General Description
Features
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
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.
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Ultra-low quiescent current (IQ = 23µA @IO = 100µA)
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
• 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
40
35
VIN
30V
MIC5239
IN
OUT
EN
FLG
GND
VOUT
3.0V/100µA
IGND = 23µA
IOUT = 100µA
25
20
15
Regulator with Low IO and Low IQ
IOUT = 1mA
30
10
4
IOUT = 10µA
9
14
19
24
29
Ground Current vs. Input Voltage
MLF and MicroLeadFrame is a registered trademark of Amkor Technologies
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
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Micrel
MIC5239
Ordering Information
Part Number
Standard
Pb-Free
Voltage(1)
Junction Temp. Range
Package
MIC5239-1.5BM
MIC5239-1.5YM
1.5V
–40°C to +125°C
8-pin SOIC
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.
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MIC5239
Pin Configuration
SOIC-8 (M)
MSOP-8(MM)
(Fixed)
SOT-223 (S)
SOIC-8 (M)
MSOP-8(MM)
(Adj)
Pin Description
Pin Number
MSOP/SOIC
Pin Number
SOT-223
Pin Name
2 (fixed)
—
FLG
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.
2 (adj)
—
ADJ
Adjustable Feedback Input: Connect to voltage divider network.
3
1
IN
4
3
OUT
1
—
EN
5–8
2
GND
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Pin Function
Power Supply Input.
Regulated Output.
Enable (input): Logic low = shutdown; logic high = enabled.
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 (VEN)............................ –0.3V to +32V
Power Dissipation (PD)(3) ...........................Internally Limited
Junction Temperature (TJ) ........................–40°C to +125°C
Storage Temperature (TS).........................–65°C to +150°C
Lead Temperature (soldering, 5 sec.)........................ 260°C
ESD Rating(4)
SOT-23-3L ............................................................... 2kV
MSOP-8L .............................................................. 1.5kV
Supply Voltage (VIN).......................................... 2.3V to 30V
Enable Input Voltage (VEN)................................... 0V to 30V
Junction Temperature (TJ) ........................ –40°C to +125°C
Package Thermal Resistance
MSOP (θJA)....................................................... 80°C/W
SOT-223 (θJA)................................................... 50°C/W
Electrical Characteristics(5)
VIN = VOUT + 1V; VEN ≥ 2.0V; IOUT = 100µA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted.
Symbol
Parameter
Condition
Min
VOUT
Output Voltage Accuracy
Variation from nominal VOUT
–1
–2
∆VOUT/VOUT
Line Regulation
VIN = VOUT +1V to 30V
∆VOUT/VOUT
∆V
IGND
Load Regulation
Dropout Voltage
(7)
Ground Pin Current
IOUT = 100µA to 500mA
(6)
Typ
Max
Units
1
2
%
%
0.06
0.5
%
15
30
mV
IOUT = 100µA
50
mV
IOUT = 150mA
260
IOUT = 500mA
350
VEN ≥ 2.0V, IOUT = 100µA
23
40
45
µA
µA
VEN ≥ 2.0V, IOUT = 150mA
1.3
5
mA
VEN ≥ 2.0V, IOUT = 500mA
8.5
15
mA
350
400
mV
mV
mV
IGND(SHDN)
Ground Pin Shutdown
VEN ≤ 0.6V, VIN = 30V
0.1
1
µA
ISC
Short Circuit Current
VOUT = 0V
850
1200
mA
en
Output Noise
10Hz to 100kHz, VOUT = 3.0V, CL = 3.3µF
160
µVrms
Low Threshold
% of VOUT
94
%
High Threshold
% of VOUT
95
%
VOL
FLAG Output Low Voltage
VIN = VOUT(nom) – 0.12VOUT, IOL = 200µA
150
mV
ILEAK
FLAG Output Leakage
VOH = 30V
0.1
µA
VIL
Input Low Voltage
regulator off
VIH
Input High Voltage
regulator on
2.0
IIN
Enable Input Current
VEN = 0.6V, regulator off
–1.0
–2.0
FLAG Output
VFLG
Enable Input
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0.6
V
V
0.01
1.0
2.0
µA
µA
VEN = 2.0V, regulator on
0.15
1.0
2.0
µA
µA
VEN = 30V, regulator on
0.5
2.5
5.0
µA
µA
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MIC5239
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. The θJA of the MIC5239x.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, 1.5kΩ 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.
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MIC5239
Typical Characteristics (VOUT = 3V)
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MIC5239
Typical Characteristics (continued) (VOUT = 3V)
Input Current
INPUT CURRENT (mA)
120
100
80
60
40
20
0
-20
VEN = 5V
RLOAD = 30
-10
0
SUPPLY VOLTAGE (V)
10
Functional Characteristics
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MIC5239
Functional Diagram
Block Diagram — Fixed Voltages
Block Diagram — Adjustable Voltages
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MIC5239
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 200kΩ pull-up
resistor tied to the input voltage.
In order to avoid output oscillations, slow transitions from
low-to-high should be avoided.
200k
V
5V 200k
FLG
GND
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 200kΩ to 1MΩ 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.
V
MIC5239
OUT
IN
EN
Figure 2. Output Capacitor ESR
V
C
Figure 1. Remote Enable
Output
Voltage
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.
0V
VALID ERROR
Error FLAG
Output
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 3.4Ω 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.
December 2007
4.75V
Input
Voltage
NOT
VALID
NOT
VALID
5V
1.3V
0V
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.
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MIC5239
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 200kΩ 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
200k
VIN
5V
VERR
MIC5239
IN
OUT
200k
EN
FLG
GND
SHUTDOWN
ENABLE
Figure 5. Thermal Resistance
Using the power MSOP-8 reduces the θJC dramatically
and allows the user to reduce θCA. The total thermal
resistance, θJA (junction-to-ambient thermal resistance)
is the limiting factor in calculating the maximum power
dissipation capability of the device. Typically, the power
MSOP-8 has a θJC of 80°C/W, this is significantly lower
than the standard MSOP-8 which is typically 200°C/W.
θCA 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.
VOUT
COUT
4.7µF
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.
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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, θJC
(junction-to-case thermal resistance) and θCA (case-toambient thermal resistance). See Figure 5. θJC is the
resistance from the die to the leads of the package. θCA
is the resistance from the leads to the ambient air and it
includes θCS (case-to-sink thermal resistance) and θSA
(sink-to-ambient thermal resistance).
Figure 6. Copper Area vs. Power-MSOP
Power Dissipation (∆TJA)
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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MIC5239
∆T = TJ(max) – TA(max)
TJ(max) = 125°C
TA(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:
Figure 8. Copper Area vs. Power-SOIC
Power Dissipation (∆TJA)
PD = (VIN – VOUT) IOUT + VIN × IGND
If we use a 3V output device and a 28V input at
moderate output current of 25mA, then our power
dissipation is as follows:
2
PD = (28V – 3V) × 25mA + 28V 250µA
PD = 625mW + 7mW
PD = 632mW
From Figure 6, the minimum amount of copper required
to operate this application at a ∆T of 75°C is 110mm2.
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 110mm2.
The θJA 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.
2
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
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
100mm2, when using the power SOIC-8.
Figure 7. Copper Area vs. Power-MSOP
Power Dissipation (TA)
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MIC5239
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:
Adjustable Regulator Application
R1 ⎞
⎛
VOUT = VREF ⎜1 +
⎟
R2
⎝
⎠
Where VREF = 1.23V.
Feedback resistor R2 should be no larger than 300kΩ.
Figure 10. Adjustable Voltage Application
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MIC5239
Package Information
8-Pin MSOP (MM)
SOT-223 (S)
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MIC5239
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
use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
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
indemnify Micrel for any damages resulting from such use or sale.
© 2003 Micrel, Incorporated.
December 2007
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