Micrel MIC29152BT High-current low-dropout regulator Datasheet

MIC29150/29300/29500/29750
High-Current Low-Dropout Regulators
General Description
Features
The MIC29150/29300/29500/29750 are high current, high
accuracy, low-dropout voltage regulators. Using Micrel's
proprietary Super βeta PNP® process with a PNP pass
element, these regulators feature 350mV to 425mV (full
load) typical dropout voltages and very low ground current.
Designed for high current loads, these devices also find
applications in lower current, extremely low dropout-critical
systems, where their tiny dropout voltage and ground
current values are important attributes.
The MIC29150/29300/29500/29750 are fully protected
against overcurrent faults, reversed input polarity, reversed
lead insertion, overtemperature operation, and positive
and negative transient voltage spikes. Five pin fixed
voltage versions feature logic level ON/OFF control and an
error flag which signals whenever the output falls out of
regulation. Flagged states include low input voltage
(dropout), output current limit, overtemperature shutdown,
and extremely high voltage spikes on the input.
On the MIC29xx1 and MIC29xx2, the ENABLE pin may be
tied to VIN if it is not required for ON/OFF control. The
MIC29150/29300/29500 are available in 3-pin and 5-pin
TO-220 and surface mount TO-263 (D2Pak) packages.
The MIC29750 7.5A regulators are available in 3-pin and
5-pin TO-247 packages. The 1.5A, adjustable output
MIC29152 is available in a 5-pin power D-Pak (TO-252)
package.
For applications with input voltage 6V or below, see
MIC37xxx LDOs.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
• High current capability
MIC29150/29151/29152/29153.................................1.5A
MIC29300/29301/29302/29303.................................... 3A
MIC29500/29501/29502/29503.................................... 5A
MIC29750/29751/29752............................................7.5A
• Low-dropout voltage
• Low ground current
• Accurate 1% guaranteed tolerance
• Extremely fast transient response
• Reverse-battery and “Load Dump” protection
• Zero-current shutdown mode (5-pin versions)
• Error flag signals output out-of-regulation (5-pin
versions)
• Also characterized for smaller loads with industryleading performance specifications
• Fixed voltage and adjustable versions
Applications
•
•
•
•
•
Battery powered equipment
High-efficiency “Green” computer systems
Automotive electronics
High-efficiency linear lower supplies
High-efficiency lost-regulator for switching supply
_________________________________________________________________________________________________________________________
Typical Application**
Fixed Output Voltage
Adjustable Output Voltage
(*See Minimum Load Current Section)
**See Thermal Design Section
Super βeta PNP is a registered trademark of Micrel, 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
May 2010
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Ordering Information
Part Number
Standard
RoHS Compliant(2)
Junction Temp.
Range(1)
Voltage
Current
Package
MIC29150-3.3BT
MIC29150-3.3WT(2)
–40°C to +125°C
3.3
1.5A
3-Pin TO-220
MIC29150-3.3BU
MIC29150-3.3WU(2)
–40°C to +125°C
3.3
1.5A
3-Pin TO-263
MIC29150-5.0BT
MIC29150-5.0WT
(2)
–40°C to +125°C
5
1.5A
3-Pin TO-220
(2)
MIC29150-5.0BU
–40°C to +125°C
5
1.5A
3-Pin TO-263
MIC29150-12BT
MIC29150-12WT
(2)
–40°C to +125°C
12
1.5A
3-Pin TO-220
MIC29150-12BU
MIC29150-12WU(2)
–40°C to +125°C
12
1.5A
3-Pin TO-263
MIC29151-3.3BT
(2)
–40°C to +125°C
3.3
1.5A
5-Pin TO-220
MIC29151-3.3BU
MIC29151-3.3WU
(2)
–40°C to +125°C
3.3
1.5A
5-Pin TO-263
MIC29151-5.0BT
MIC29151-5.0WT(2)
–40°C to +125°C
5
1.5A
5-Pin TO-220
MIC29151-5.0BU
(2)
MIC29151-12BT
MIC29150-5.0WU
MIC29151-3.3WT
MIC29151-5.0WU
MIC29151-12WT
–40°C to +125°C
5
1.5A
5-Pin TO-263
(2)
–40°C to +125°C
12
1.5A
5-Pin TO-220
(2)
MIC29151-12BU
MIC29151-12WU
–40°C to +125°C
12
1.5A
5-Pin TO-263
MIC29152BT
MIC29152WT(2)
–40°C to +125°C
Adj.
1.5A
5-Pin TO-220
MIC29152BU
MIC29152WU(2)
–40°C to +125°C
Adj.
1.5A
5-Pin TO-263
—
(2)
MIC29152WD
–40°C to +125°C
Adj.
1.5A
5-Pin TO-252
MIC29153BT(3)
Contact Factory
–40°C to +125°C
Adj.
1.5A
5-Pin TO-220
MIC29153BU(3)
Contact Factory
–40°C to +125°C
Adj.
1.5A
5-Pin TO-263
(2)
–40°C to +125°C
3.3
3.0A
3-Pin TO-220
MIC29300-3.3BU
MIC29300-3.3WU
(2)
–40°C to +125°C
3.3
3.0A
3-Pin TO-263
MIC29300-5.0BT
MIC29300-5.0WT(2)
–40°C to +125°C
5
3.0A
3-Pin TO-220
MIC29300-5.0BU
(2)
MIC29300-3.3BT
MIC29300-3.3WT
–40°C to +125°C
5
3.0A
3-Pin TO-263
MIC29300-12BT
MIC29300-12WT
(2)
–40°C to +125°C
12
3.0A
3-Pin TO-220
MIC29300-12BU
MIC29300-12WU(2)
–40°C to +125°C
12
3.0A
3-Pin TO-263
MIC29301-3.3BT
(2)
–40°C to +125°C
3.3
3.0A
5-Pin TO-220
(2)
–40°C to +125°C
3.3
3.0A
5-Pin TO-263
MIC29301-3.3BU
MIC29300-5.0WU
MIC29301-3.3WT
MIC29301-3.3WU
MIC29301-5.0BT
MIC29301-5.0WT
(2)
–40°C to +125°C
5
3.0A
5-Pin TO-220
MIC29301-5.0BU
MIC29301-5.0WU(2)
–40°C to +125°C
5
3.0A
5-Pin TO-263
MIC29301-12BT
MIC29301-12WT(2)
–40°C to +125°C
12
3.0A
5-Pin TO-220
MIC29301-12BU
MIC29301-12WU
(2)
–40°C to +125°C
12
3.0A
5-Pin TO-263
MIC29302BT
MIC29302WT(2)
–40°C to +125°C
Adj.
3.0A
5-Pin TO-220
MIC29302BU
MIC29302WU(2)
–40°C to +125°C
Adj.
3.0A
5-Pin TO-263
MIC29303BT
(2)
–40°C to +125°C
Adj.
3.0A
5-Pin TO-220
(2)
MIC29303WT
MIC29303BU
MIC29303WU
–40°C to +125°C
Adj.
3.0A
5-Pin TO-263
MIC29500-3.3BT
MIC29500-3.3WT(2)
–40°C to +125°C
3.3
5.0A
3-Pin TO-220
MIC29500-5.0BT
MIC29500-5.0WT(2)
–40°C to +125°C
5
5.0A
3-Pin TO-220
MIC29501-3.3BT
MIC29501-3.3WT
(2)
–40°C to +125°C
3.3
5.0A
5-Pin TO-220
MIC29501-3.3BU
MIC29501-3.3WU(2)
–40°C to +125°C
3.3
5.0A
5-Pin TO-263
MIC29501-5.0BT
MIC29501-5.0WT(2)
–40°C to +125°C
5
5.0A
5-Pin TO-220
MIC29501-5.0BU
MIC29501-5.0WU
(2)
–40°C to +125°C
5
5.0A
5-Pin TO-263
MIC29502BT
MIC29502WT(2)
–40°C to +125°C
Adj.
5.0A
5-Pin TO-220
May 2010
2
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Part Number
RoHS Compliant(2)
Standard
Junction Temp.
Range(1)
Voltage
Current
Package
MIC29502BU
MIC29502WU(2)
–40°C to +125°C
Adj.
5.0A
5-Pin TO-263
MIC29503BT
MIC29503WT(2)
–40°C to +125°C
Adj.
5.0A
5-Pin TO-220
MIC29503BU
MIC29503WU
(2)
–40°C to +125°C
Adj.
5.0A
5-Pin TO-263
MIC29750-3.3BWT
Contact Factory
–40°C to +125°C
3.3
7.5A
3-Pin TO-247
MIC29750-5.0BWT
Contact Factory
–40°C to +125°C
5
7.5A
3-Pin TO-247
MIC29751-3.3BWT
Contact Factory
–40°C to +125°C
3.3
7.5A
5-Pin TO-247
MIC29751-5.0BWT
Contact Factory
–40°C to +125°C
5
7.5A
5-Pin TO-247
–40°C to +125°C
Adj.
7.5A
5-Pin TO-247
MIC29752BWT
MIC29752WWT
(2)
Note:
1. Junction Temperature
2. RoHS compliant with ‘high-melting solder’ exemption.
3. Special Order, Contact Factory
Pin Configuration
May 2010
3-Pin TO-220 (T)
MIC29150/29300/29500
5-Pin TO-220 Fixed Voltage (T)
MIC29151/29301/29501/29751
5-Pin TO-220 Adjustable Voltage (T)
MIC29152/29302/29502
5-Pin TO-220 Adjustable with Flag (T)
MIC29153/29303/29503
3-Pin TO-247 (WT)
MIC29750
5-Pin TO-247 Fixed Voltage (WT)
MIC29751
5-Pin TO-247 Adjustable Voltage (WT)
MIC29752
3-Pin TO-263 (D2Pak) (UT)
MIC29150/29300
3
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
5-Pin TO-263 (D2Pak) Fixed Voltage (U)
MIC29151/29301/29501
5-Pin TO-263 (D2Pak) Adjustable Voltage (U)
MIC29302/29502
5-Pin TO-263 (D2Pak) Adjustable with Flag (U)
MIC29153/29303/29503
5-Pin TO-252 (D-Pak) Adjustable Voltage (D)
MIC29152
Pin Description
Pin Number
TO-220
TO-247
TO-263
Pin Name
1
INPUT: Supplies the current to the output power device
2
GND: TAB is also connected internally to the IC’s ground on D-PAK.
3
OUTPUT: The regulator output voltage
Pin Description
Pin Number
Fixed
TO-220
TO-247
TO-263
Pin Number
Adjustable
TO-220
TO-247
TO-252
TO-263
Pin Number
Adj. with Flag
TO-220
TO-247
TO-263
1
1
—
Pin Name
ENABLE: CMOS compatible control input.
Logic high = enable, logic low = shutdown.
2
2
2
3, TAB
3, TAB
3, TAB
4
4
4
OUTPUT: The regulator output voltage
—
5
5
ADJUST: Adjustable regulator feedback input that connects to the resistor
voltage divider that is placed from OUTPUT to GND in order to set the
output voltage.
5
—
1
FLAG: Active low error flag output signal that indicates an output fault
condition
May 2010
INPUT: Supplies the current to the output power device
GND: TAB is also connected internally to the IC’s ground on D-PAK.
4
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Absolute Maximum Ratings(1)
Operating Ratings(2)
Input Supply Voltage (VIN)(1) ........................... –20V to +60V
Enable Input Voltage (VEN)................................ –0.3V to VIN
Lead Temperature (soldering, 5sec.)......................... 260°C
Power Dissipation .....................................Internally Limited
Storage Temperature Range ....................–65°C to +150°C
ESD Rating................................................................ Note 3
Operating Junction Temperature .............. –40°C to +125°C
Maximum Operating Input Voltage ................................26V
Package Thermal Resistance
TO-220 (θJC).........................................................2°C/W
TO-263 (θJC).........................................................2°C/W
TO-247 (θJC) .....................................................1.5°C/W
TO-252 (θJC).........................................................3°C/W
TO-252 (θJA) ......................................................56°C/W
Electrical Characteristics(4,13)
VIN = VOUT + 1V; IOUT = 10mA; TJ = 25°C, bold values indicate –40°C≤ TJ ≤ +125°C, unless noted.
Parameter
Condition
Output Voltage
IOUT = 10mA
Min
Max
Units
–1
1
%
–2
2
%
0.06
0.5
%
0.2
1
%
20
100
ppm/°C
IOUT = 100mA
IOUT = 750mA
IOUT = 1.5A
IOUT = 100mA
IOUT = 1.5A
IOUT = 3A
IOUT = 250mA
IOUT = 2.5A
IOUT = 5A
IOUT = 250mA
IOUT = 4A
IOUT = 7.5A
80
220
350
80
250
370
125
250
370
80
270
425
200
mV
IOUT = 750mA, VIN = VOUT + 1V
IOUT = 1.5A
IOUT = 1.5A, VIN = VOUT + 1V
IOUT = 3A
IOUT = 2.5A, VIN = VOUT + 1V
IOUT = 5A
IOUT = 4A, VIN = VOUT + 1V
IOUT = 7.5A
8
22
10
37
15
70
35
120
20
mA
35
mA
50
mA
75
mA
IGRNDDOGround Pin
Current at Droupout
VIN = 0.5V less than specified VOUT × IOUT = 10mA
MIC29150
MIC29300
MIC29500
MIC29750
0.9
1.7
2.1
3.1
Current Limit
MIC29150
MIC29300
MIC29500
MIC29750
10mA ≤ IOUT ≤ IFL, (VOUT + 1V) ≤ VIN ≤26V
Line Regulation
Load Regulation
IOUT = 10mA, (VOUT + 1V) ≤ VIN ≤26V
VIN = VOUT + 5V, 10mA ≤ IOUT ≤ 1.5A
Output Voltage
Temperature Coefficient.
Dropout Voltage
∆VOUT = -1% (6)
MIC29150
MIC29300
MIC29500
MIC29750
MIC29150
MIC29300
MIC29500
MIC29750
Note 8
May 2010
(5,9)
(9)
∆VO
∆T
Ground Current
(5)
VOUT = 0V (7)
VOUT = 0V (7)
VOUT = 0V (7)
VOUT = 0V (7)
Typ
2.1
4.5
7.5
9.5
5
600
175
600
250
600
200
750
mA
mA
mA
mA
3.5
5.0
10.0
15
A
A
A
A
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Parameter
Condition
en, Output Noise
Voltage
(10Hz to 100kHz)
IL = 100mA
CL = 10µF
400
CL = 33µF
260
Ground Current in
Shutdown
Reference
Min
MIC29150/1/2/3 only VEN = 0.4V
Max
Units
µV
(rms)
2
10
30
µA
µA
1.240
1.252
1.265
V
V
1.277
V
80
120
nA
MIC29xx2/MIC29xx3
Reference Voltage
1.228
1.215
Reference Voltage
1.203
Adjust Pin
Bias Current
Reference Voltage
Temperature
Coefficient
Typ
40
(10)
Adjust Pin Bias
Current
Temperature
Coefficient
20
ppm/°C
0.1
nA/°C
Flag Output (Error Comparator) MIC29xx1/29xx3
Output Leakage
Current
VOH = 26V
0.01
1.00
2.00
µA
Output Low Voltage
Device set for 5V, VIN = 4.5V
IOL = 250µA
220
300
400
mV
Upper Threshold
Voltage
Device set for 5V (11)
Lower Threshold
Voltage
Device set for 5V (11)
75
Hysteresis
Device set for 5V (11)
15
ENABLE Input
40
25
95
140
mV
mV
V
0.8
2.4
VEN = 26V
Input Current
VEN = 0.8V
Regulator Output
Current in Shutdown
(12)
May 2010
mV
MIC29xx1/MIC29xx2
Input Logic Voltage
Low (OFF)
High (ON)
Enable Pin
60
100
0.7
10
6
600
750
µA
2
4
µA
500
µA
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Notes:
1.
Maximum positive supply voltage of 60V must be of limited duration (<100msec) and duty cycle (≤1%). The maximum continuous supply voltage is
26V. Exceeding the absolute maximum rating may damage the device.
2.
The device is not guaranteed to function outside its operating rating.
3.
Devices are ESD sensitive. Handling precautions recommended.
4.
Specification for packaged product only.
5.
Full load current (IFL) is defined as 1.5A for the MIC29150, 3A for the MIC29300, 5A for the MIC29500, and 7.5A for the MIC29750 families.
6.
Dropout voltage is defined as the input-to-output differential when the output voltage drops to 99% of its normal value with VOUT + 1V applied to VIN.
7.
VIN = VOUT (nominal) + 1V. For example, use VIN = 4.3V for a 3.3V regulator or use 6V for a 5V regulator. Employ pulse-testing procedures to pin
current.
8.
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 pin
current.
9.
Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
10. Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line
regulation effects. Specifications are for a200mA load pulse at VIN = 20V (a 4W pulse) for T = 10ms.
11. Comparator thresholds are expressed in terms of a voltage differential at the Adjust terminal below the nominal reference voltage measured at 6V
input. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = VOUT/VREF = (R1 + R2)/R2. For example,
at a programmed output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95mV x 5V/1.240V = 384mV. Thresholds
remain constant as a percent of VOUT as VOUT is varied, with the dropout warning occurring at typically 5% below nominal, 7.7% guaranteed.
12. VEN ≤ 0.8V and VIN ≤ 26V, VOUT = 0.
13. When used in dual supply systems where the regulator load is returned to a negative supply, the output voltage must be diode clamped to ground.
May 2010
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Micrel, Inc.
MIC29150/29300/29500/29750
Typical Characteristics MIC2915x
May 2010
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Micrel, Inc.
May 2010
MIC29150/29300/29500/29750
9
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MIC29150/29300/29500/29750
Typical Characteristics MIC2930x
May 2010
10
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Micrel, Inc.
May 2010
MIC29150/29300/29500/29750
11
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Micrel, Inc.
MIC29150/29300/29500/29750
Typical Characteristics MIC2950x
May 2010
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Micrel, Inc.
May 2010
MIC29150/29300/29500/29750
13
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Micrel, Inc.
MIC29150/29300/29500/29750
Typical Characteristics MIC2975x
May 2010
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May 2010
MIC29150/29300/29500/29750
15
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MIC29150/29300/29500/29750
Functional Diagram
May 2010
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Micrel, Inc.
MIC29150/29300/29500/29750
• Output Current, IOUT
• Output Voltage, VOUT
• Input Voltage, VIN
First, we calculate the power dissipation of the regulator
from these numbers and the device parameters from this
datasheet.
Application Information
The
MIC29150/29300/29500/29750
are
high
performance low-dropout voltage regulators suitable for
all moderate to high-current voltage regulator
applications. Their 350mV to 425mV typical dropout
voltage at full load make them especially valuable in
battery powered systems and as high efficiency noise
filters in “post-regulator” applications. Unlike older NPNpass transistor designs, where the minimum dropout
voltage is limited by the base-emitter voltage drop and
collector-emitter saturation voltage, dropout performance
of the PNP output of these devices is limited merely by
the low VCE saturation voltage.
A trade-off for the low-dropout voltage is a varying base
driver requirement. But Micrel’s Super ßeta PNP®
process reduces this drive requirement to merely 1% of
the load current.
The MIC29150/29300/29500/29750 family of regulators
are fully protected from damage due to fault conditions.
Current limiting is provided. This limiting is linear; output
current under overload conditions is constant. Thermal
shutdown disables the device when the die temperature
exceeds the 125°C maximum safe operating
temperature. Transient protection allows device (and
load) survival even when the input voltage spikes
between –20V and +60V. When the input voltage
exceeds about 35V to 40V, the over voltage sensor
temporarily disables the regulator. The output structure
of these regulators allows voltages in excess of the
desired output voltage to be applied without reverse
current flow. MIC29xx1 and MIC29xx2 versions offer a
logic level ON/OFF control: when disabled, the devices
draw nearly zero current.
An additional feature of this regulator family is a common
pinout: a design’s current requirement may change up or
down yet use the same board layout, as all of these
regulators have identical pinouts.
PD = IOUT (1.01 VIN − VOUT )
Where the ground current is approximated by 1% of IOUT.
Then the heat sink thermal resistance is determined with
this formula:
T
− TA
θSA = JMAX
− (θJC + θCS )
PD
Where TJMAX ≤ 125°C and θCS is between 0 and 2°C/W.
The heat sink may be significantly reduced in
applications where the minimum input voltage is known
and is large compared with the dropout voltage. Use a
series input resistor to drop excessive voltage and
distribute the heat between this resistor and the
regulator. The low-dropout properties of Micrel Super
ßeta PNP® regulators allow very significant reductions in
regulator power dissipation and the associated heat sink
without compromising performance. When this technique
is employed, a capacitor of at least 0.1µF is needed
directly between the input and regulator ground.
Please refer to Application Note 9 and Application Hint
17 for further details and examples on thermal design
and heat sink specification.
With no heat sink in the application, calculate the
junction temperature to determine the maximum power
dissipation that will be allowed before exceeding the
maximum junction temperature of the MIC29152. The
maximum power allowed can be calculated using the
thermal resistance (θJA) of the D-Pak adhering to the
following criteria for the PCB design: 2 oz. copper and
100mm2 copper area for the MIC29152.
For example, given an expected maximum ambient
temperature (TA) of 75°C with VIN = 3.3V, VOUT = 2.5V,
and IOUT = 1.5A, first calculate the expected PD using
Equation (1);
PD=(3.3V–2.5V)1.5A–(3.3V)(0.016A)=1.1472W
Next, calcualte the junction temperature for the expected
power dissipation.
MIC29XXX
VIN
OUT
IN
VOUT
GND
TJ=(θJA×PD)+TA=(56°C/W×1.1472W)+75°C=139.24°C
Now determine the maximum power dissipation allowed
that would not exceed the IC’s maximum junction
temperature (125°C) without the useof a heat sink by
Figure 3. Linear regulators require only two capacitors for
operation.
Thermal Design
Linear regulators are simple to use. The most
complicated design parameters to consider are thermal
characteristics. Thermal design requires the following
application-specific parameters:
PD(MAX)=(TJ(MAX)–TA)/θJA=(125°C–75°C)/(56°C/W) =0.893W
• Maximum ambient temperature, TA
May 2010
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Micrel, Inc.
MIC29150/29300/29500/29750
Adjustable Regulator Design
Capacitor Requirements
For stability and minimum output noise, a capacitor on
the regulator output is necessary. The value of this
capacitor is dependent upon the output current; lower
currents
allow
smaller
capacitors.
The
MIC29150/29300/29500/29750 regulators are stable
with the following minimum capacitor values at full load:
Device
Full Load Capacitor
MIC29150...............................................10µF
MIC29300...............................................10µF
MIC29500...............................................10µF
MIC29750...............................................22µF
This capacitor need not be an expensive low ESR type:
aluminum electrolytics are adequate. In fact, extremely
low ESR capacitors may contribute to instability.
Tantalum capacitors are recommended for systems
where fast load transient response is important.
Where the regulator is powered from a source with a
high AC impedance, a 0.1µF capacitor connected
between Input and GND is recommended. This capacitor
should have good characteristics to above 250kHz.
MIC29152BT
VIN
VOUT
R1
10µF
22µF
R2
Figure 4. Adjustable Regulator with Resistors
The adjustable regulator versions, MIC29xx2 and
MIC29xx3, allow programming the output voltage
anywhere between 1.25V and the 25V. Two resistors are
used. The resistor values are calculated by:
Minimum Load Current
The MIC29150–29750 regulators are specified between
finite loads. If the output current is too small, leakage
currents dominate and the output voltage rises. The
following minimum load current swamps any expected
leakage current across the operating temperature range:
Device
Minimum Load
MIC29150................................................5mA
MIC29300................................................7mA
MIC29500..............................................10mA
MIC29750..............................................10mA
⎞
⎛V
R 1 = R 2 × ⎜⎜ OUT − 1⎟⎟
1.240
⎠
⎝
where VOUT is the desired output voltage. Figure 4 shows
component definition. Applications with widely varying
load currents may scale the resistors to draw the
minimum load current required for proper operation (see
“Minimum Load Current” section).
Error Flag
MIC29xx1 and MIC29xx3 versions feature an Error Flag,
which looks at the output voltage and signals an error
condition when this voltage drops 5% below its expected
value. The error flag is an open-collector output that
pulls low under fault conditions. It may sink 10mA. Low
output voltage signifies a number of possible problems,
including an overcurrent fault (the device is in current
limit) and low input voltage. The flag output is inoperative
during overtemperature shutdown conditions.
Enable Input
MIC29xx1 and MIC29xx2 versions feature an enable
(EN) input that allows ON/OFF control of the device.
Special design allows “zero” current drain when the
device is disabled—only microamperes of leakage
current flows. The EN input has TTL/CMOS compatible
thresholds for simple interfacing with logic, or may be
directly tied to ≤30V. Enabling the regulator requires
approximately 20µA of current.
May 2010
18
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Package Information
3-Pin TO-220 (T)
5-Pin TO-220 (T)
May 2010
19
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
5-Pin TO-263 (U)
3-Pin TO-263 (U)
May 2010
20
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
5-Pin TO-247 (WT)
3-Pin TO-247 (WT)
May 2010
21
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
5-Pin TO-252 (D)
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.
© 2009 Micrel, Incorporated.
May 2010
22
M9999-050510-B
Micrel, Inc.
MIC29150/29300/29500/29750
Revision History
Date
Change Description/Edits by:
Revisions
6/18/08
Locked document. M.Mclean
15
5/28/09
Unlocked document, removed some styles, minor formatting. M.Galvan
16
6/3/09
Fixed EC table font from 10pst to pts, moved Typ. App. drwg to front page
7/23/09
Edited EC table and diagrams, added pin descriptions.
072309_AMSr1
9/18/09
Added EVB Circuit and BOM. Text added to Thermal Design section
091809_AMS
9/22/09
Removed EVB Circuit and BOM
092409_AMS
10/12/09
Update drawings and curves
Martha taken
over for Mike
May 2010
23
M9999-050510-B
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