MIC2920A/29201/29202/29204
Micrel, Inc.
MIC2920A/29201/29202/29204
400mA Low-Dropout Voltage Regulator
General Description
The MIC2920A family are “bulletproof,” efficient voltage regu-
lators with very low dropout voltage (typically 40mV at light
loads and 370mV at 250mA), and very low quiescent current
(140µA typical). The quiescent current of the MIC2920A in-
creases only slightly in dropout, prolonging battery life. Key
MIC2920A features include protection against reversed bat-
tery, fold-back current limiting, and automotive “load dump”
protection (60V positive transient).
The MIC2920 is available in several configurations. The
MIC2920A-x.x devices are three pin fixed voltage regulators
available in 3.3V, 4.85V, 5V, and 12V outputs. The MIC29201
is a fixed regulator offering a logic compatible ON/OFF (shut-
down) input and an error flag output. This flag may also be
used as a power-on reset signal. A logic-compatible shutdown
input is provided on the adjustable MIC29202 which allows
the regulator to be switched on and off. The MIC29204 8-pin
SOIC adjustable regulator includes both shutdown and error
flag pins and may be pin-strapped for 5V output or programmed
from 1.24V to 26V using two external resistors.
Features
•
•
•
•
•
•
•
•
•
•
•
•
High output voltage accuracy
Guaranteed 400mA output
Low quiescent current
Low dropout voltage
Extremely tight load and line regulation
Very low temperature coefficient
Current and thermal limiting
Input withstands –20V reverse battery and
60V positive transients
Error flag warns of output dropout
Logic-controlled electronic shutdown
Output programmable from 1.24V to 26V
(MIC29202/MIC29204)
Available in TO-220-3, TO-220-5, and surface-mount
TO-263-5, SOT-223, and SO-8 packages.
Battery-powered equipment
Cellular telephones
Laptop, notebook, and palmtop computers
PCMCIA V
CC
and V
PP
regulation/switching
Bar code scanners
Automotive electronics
SMPS post-regulators
Voltage reference
High-efficiency linear power supplies
Applications
•
•
•
•
•
•
•
•
•
Pin Configuration
TAB
TAB
TAB
OUTPUT
1
SENSE
2
SHUTDOWN
3
GROUND
4
8
INPUT
7
NC
6
NC
5
ERROR
1
2
3
MIC29201-3.3BM (SOIC-8)
OUTPUT
1
SENSE
2
SHUTDOWN
3
GROUND
4
INPUT
OUTPUT
GROUND
8
INPUT
7
A D JUST
6
5V TAP
5
ERROR
MIC2920A-x.xBS
(SOT-223)
TAB
MIC29204BM (SOIC-8)
5-Lead Package Pinouts
MIC29201 MIC29202
1) Error
Adjust
2) Input
Shutdown
3) Ground
Ground
4) Output
Input
5) Shutdown
Output
1
IN
1 2 3 4 5
3
OU T
GND
2
MIC29201/29202BU
(TO-263-5)
MIC2920A-xxBT
(TO-220)
MIC29201/29202BT
(TO-220-5)
1 2 3 4 5
Tab is Ground on SOT-223, TO-220, and TO-263 packages.
1
M9999-021505
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
February 2005
MIC2920A/29201/29202/29204
Micrel, Inc.
Voltage
3.3V
3.3V
4.85V
4.85V
5.0V
5.0V
12V
12V
3.3V
3.3V
3.3V
4.85V
4.85V
5.0V
5.0V
12V
12V
Adj
Adj
5V and Adj
5V and Adj
Junction Temp. Range
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
Package
SOT-223
TO-220-3
SOT-223
TO-220-3
SOT-223
TO-220-3
SOT-223
TO-220-3
SO-8
TO-220-5
TO-263-5
TO-220-5
TO-263-5
TO-220-5
TO-263-5
TO-220-5
TO-263-5
TO-220-5
TO-263-5
SO-8
8-pin PDIP
Ordering Information
Part Number
Standard
MIC2920A-3.3BS
MIC2920A-3.3BT
MIC2920A-4.8BS
MIC2920A-4.8BT
MIC2920A-5.0BS
MIC2920A-5.0BT
MIC2920A-12BS
MIC2920A-12BT
MIC29201-3.3BM
MIC29201-3.3BT
MIC29201-3.3BU
MIC29201-4.8BT
MIC29201-4.8BU
MIC29201-5.0BT
MIC29201-5.0BU
MIC29201-12BT
MIC29201-12BU
MIC29202BT
MIC29202BU
MIC29204BM
MIC29204BN
Pb-Free
MIC2920A-3.3WS*
MIC2920A-3.3WT*
MIC2920A-4.8WS*
MIC2920A-4.8WT*
MIC2920A-5.0WS*
MIC2920A-5.0WT*
MIC2920A-12WS*
MIC2920A-12WT*
MIC29201-3.3YM
MIC29201-3.3WT*
MIC29201-3.3WU*
MIC29201-4.8WT*
MIC29201-4.8WU*
MIC29201-5.0WT*
MIC29201-5.0WU*
MIC29201-12WT*
MIC29201-12WU*
MIC29202WT*
MIC29202WU*
MIC29204YM
MIC29204YN
* Pb-Free RoHS compliant with high-melting solder exemption.
M9999-021505
2
February 2005
MIC2920A/29201/29202/29204
Micrel, Inc.
Absolute Maximum Ratings
Input Supply Voltage .................................................–20V to +60V
Adjust Input Voltage (Notes 9 and 10) ......................–1.5V to +26V
Power Dissipation ................................... Internally Limited,
Note 1
Operating Junction Temperature Range ............. –40°C to +125°C
Lead Temperature (Soldering, 5 seconds) ............................260°C
Storage Temperature Range ............................... –65°C to +150°C
If Military/Aerospace specified devices are required, contact your local
Micrel representative/distributor for availability and specifications.
Operating Ratings
Operating Input Supply Voltage ......................................2V
†
to 26V
Adjust Input Voltage (Notes 9 and 10) ......................–1.5V to +26V
Shutdown Input Voltage ..........................................–0.3V to +30V
Error Comparator Output Voltage ............. –0.3V to +30VOperating
Junction Temperature Range ............................. –40°C to +125°C
Thermal Characteristics:
SOT−223 θ
JC
.............................................................. 15°C/W
TO-220 θ
JC
................................................................... 3°C/W
TO-263 θ
JC
................................................................... 3°C/W
8-Pin SOIC θ
JA
.............................................................Note
1
Across the full operating temperature, the minimum input voltage range for
full output current is 4.3V to 26V. Output will remain in-regulation at lower
output voltages and low current loads down to an input of 2V at 25°C.
†
Electrical Characteristics
Limits in standard typeface are for T
J
= 25°C and limits in boldface apply over the full operating temperature range. Unless otherwise
specified, V
IN
= V
OUT
+ 1V, I
L
= 1mA, C
L
= 10µF. Adjustable versions are set for an ouptu of 5V. The MIC29202 V
SHUTDOWN
≤ 0.7V. The
eight pin MIC29204 is configured with the Adjust pin tied to the 5V Tap, the Output is tied to Output Sense (V
OUT
= 5V), and V
SHUTDOWN
≤
0.7V.
Symbol
V
O
Parameter
Output Voltage
Accuracy
Conditions
Variation from factory trimmed V
OUT
1mA ≤ I
L
≤ 400mA, across temp. range
MIC2920A-12 and 29201-12 only
1mA ≤ I
L
≤ 400mA, across temp. range
∆V
O
∆T
∆V
O
V
O
∆V
O
V
O
V
IN
- V
O
Output Voltage
Temperature Coef.
Line Regulation
Load Regulation
Dropout Voltage
(Note 4)
(Note 2)
V
OUT
> 10V only
V
IN
= V
OUT
+ 1V to 26V
IL = 1 to 250mA (Note 3)
I
L
= 1mA
I
L
= 100mA
I
L
= 250mA
I
L
= 400mA
I
GND
Ground Pin Current
(Note 5)
I
L
= 1mA
I
L
= 100mA
I
L
= 250mA
I
L
= 400mA
I
GNDDO
I
LIMIT
∆V
O
∆P
D
e
n
Ground Pin Current
at Dropout
(Note 5)
Current Limit
Thermal Regulation
Output Noise Voltage
(10Hz to 100kHz)
IL = 100mA
V
IN
= 0.5V less than designed V
OUT
(V
OUT
= 3.3V)
I
O
= 1mA
V
OUT
= 0V
(Note 6)
(Note 7)
CL = 10µF
CL = 100µF
V
OUT
> 10V only
V
OUT
> 10V only
Min
-1
-2
-2.5
-1.5
-3
-4
20
80
0.03
0.04
100
250
350
370
500
400
140
1.3
5
13
180
Typ
Max
1
2
2.5
1.5
3
4
100
350
0.10
0.40
0.16
0.30
150
180
%
%
mV
ppm/°C
Units
%
600
750
200
300
2
2.5
9
12
15
400
µA
mA
µA
425
0.05
400
260
100
1200
0.2
mA
%/W
µV RMS
February 2005
3
M9999-021505
MIC2920A/29201/29202/29204
Parameter
MIC29202, MIC29204
Reference Voltage
Reference Voltage
Reference Voltage
Reference Voltage
Adjust Pin
Bia Current
Reference Voltage
Temperature
Coefficient
Adjust Pin Bias
Current Temperature
Coefficient
Error Comparator
Output Leakage
Current
Output Low
Voltage
Upper Threshold
Voltage
Lower Threshold
Voltage
Hysteresis
Shutdown Input
Input Logic Voltage
MIC29201, MIC29204
V
OH
= 26V
V
IN
= 4.5V
I
OL
= 250µA
(Note 9)
(Note 9)
(Note 9)
MIC29201, MIC29202, MIC29204
Low (ON)
High (OFF)
V
SHUTDOWN
= 2.4V
V
SHUTDOWN
= 26V
Regulator Output
Current in Shutdown
(Note 10)
1.3
2.0
30
450
3
0.7
50
100
600
750
10
20
40
25
0.01
150
60
75
15
95
140
1.00
2.00
250
400
(Note 7)
MIC29202
MIC29202 (Note 8)
MIC29204
MIC29204 (Note 8)
1.223
1.210
1.204
1.210
1.200
1.185
20
20
1.235
1.235
1.247
1.260
1.266
1.260
1.270
1.285
40
60
Conditions
Min
Typ
Max
Micrel, Inc.
Units
V
V
V
V
nA
ppm/°C
0.1
nA/°C
µA
mV
mV
mV
mV
V
Shutdown Pin
Input Current
µA
µA
µA
M9999-021505
4
February 2005
MIC2920A/29201/29202/29204
Notes:
General:
Note 1:
Micrel, Inc.
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
Note 10:
Note 11:
Note 12:
Devices are ESD protected; however, handling precautions are recommended.
Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when
operating the device outside of its rated operating conditions. The maximum allowable power dissipation is a function of the maximum
junction temperature, T
J (MAX)
, the junction-to-ambient thermal resistance, θ
JA
, and the ambient temperature, T
A
. The maximum allowable
power dissipation at any ambient temperature is calculated using: P
(MAX)
= (T
J(MAX)
– T
A
) / θ
JA.
Exceeding the maximum allowable power
dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The junction to ambient thermal
resistance of the MIC29204BM is 160°C/W mounted on a PC board.
Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
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.
Dropout Voltage is defined as the input to output differential at which the output voltage drops 100mV below its nominal value measured at
1V differential. At low values of programmed output voltage, the minimum input supply voltage of 4.3V over temperature must be taken into
account. The MIC2920A operates down to 2V of input at reduced output current at 25°C.
Ground pin current is the regulator quiescent current. The total current drawn from the supply is the sum of the load current plus the ground
pin current.
The MIC2920A features fold-back current limiting. The short circuit (V
OUT
= 0V) current limit is less than the maximum current with normal
output voltage.
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 a 200mA load pulse at V
IN
= 20V (a 4W pulse) for T = 10ms.
V
REF
≤ V
OUT
≤ (V
IN
– 1 V), 4.3V ≤ V
IN
≤ 26V, 1 mA < I
L
≤400 mA, T
J
≤ T
J MAX.
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 = V
OUT
/V
REF
= (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 95 mV x 5V/1.235 V
= 384 mV. 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.
V
SHUTDOWN
≥ 2V, V
IN
≤ 26V,V
OUT
= 0, with Adjust pin tied to 5V Tap or to the R1, R2 junction (see Figure 3) with R1 ≥ 150kΩ.
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.
Maximum positive supply voltage of 60V must be of limited duration (< 100ms) and duty cycle ( ≤ 1%). The maximum continuous supply
voltage is 26V.
Schematic Diagram
IN
ADJUST
R18
20kΩ
Q15A
Q15B
Q24
Q26
Q25
OUT
Q9
Q3
R11
18
kΩ
Q4
Q7
Q5
SENSE
Q8
Q6
Q1
C1
20
pF
R11
20.6
kΩ
Q2
Q20
R8
31.4 kΩ
Q16
Q17
Q14
R17
12 kΩ
R27
V TAP
R28
10
R1
20 kΩ
Q42
R10
150
kΩ
Q22
Q21
C2
40 pF
Q23
R2
50 kΩ
R5
180
kΩ
R6
140
kΩ
Q13
Q12
R9
27.8 kΩ
R15
100 kΩ
Q40
R12
110
kΩ
Q11
R13
100
kΩ
R14
350
kΩ
Q29
Q41
R16
30 kΩ
R17
10
Ω
R30
30
kΩ
Q18
Q19
R3
50 kΩ
R4
13 kΩ
Q28
R21 8
Ω
50 kΩ
Q37
Q36
Q30
Q31
SHDN
R24
50 kΩ
R23 60 kΩ
10 kΩ
R22
150 kΩ
ERROR
Q38
R26
60 kΩ
Q34
R25
2.8 kΩ
D E NO T E S CO NNE CT I O N O N
MIC2920A-xx AND MIC29201-xx
VERSIONS ONLY
Q39
GND
February 2005
5
M9999-021505
嵌入式系统
