MIC5256
150mA µCap LDO with Error Flag
General Description
The MIC5256 is an efficient, precise CMOS voltage
regulator. It offers better than 1% initial accuracy,
extremely low-dropout voltage (typically 135mV at 150mA)
and low ground current (typically 90µA) over load. The
MIC5256 features an error flag that indicates an output
fault condition such as overcurrent, thermal shutdown and
dropout.
Designed specifically for handheld and battery-powered
devices, the MIC5256 provides a TTL-logic-compatible
enable pin. When disabled, power consumption drops
nearly to zero.
The MIC5256 also works with low-ESR ceramic
capacitors, reducing the amount of board space necessary
for power applications, critical in hand-held wireless
devices.
Key features include current limit, thermal shutdown, faster
transient response, and an active clamp to speed up
®
device turnoff. Available in the IttyBitty SOT-23-5
package and the new Thin SOT-23-5, which offers the
same footprint as the standard IttyBitty
®
SOT-23-5, but
only 1mm tall. The MIC5256 offers a range of output
voltages.
Data sheets and support documentation can be found on
Micrel’s web site at
www.micrel.com.
Features
•
•
•
•
•
•
Input voltage range: 2.7V to 6.0V
Thin SOT package: 1mm height
Error flag indicates fault condition
Stable with ceramic output capacitor
Ultralow dropout: 135mV @ 150mA
High output accuracy:
– 1.0% initial accuracy
– 2.0% over temperature
Low quiescent current:90µA
Tight load and line regulation
Thermal-shutdown and current-limit protection
“Zero” off-mode current
TTL logic-controlled enable input
•
•
•
•
•
Applications
•
•
•
•
•
Cellular phones and pagers
Cellular accessories
Battery-powered equipment
Laptop, notebook, and palmtop computers
Consumer/personal electronics
___________________________________________________________________________________________________________
Typical Application
Low-Noise Regulator Application
IttyBitty 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
August 2010
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M9999-080510
Micrel, Inc.
MIC5256
Absolute Maximum Ratings
(1)
Supply Voltage (V
IN
) ............................................. 0V to +7V
Enable Voltage (V
EN
)............................................ 0V to +7V
Power Dissipation (P
D
) ........................... Internally Limited
(3)
Junction Temperature (T
J
) ........................–40°C to +125°C
Storage Temperature (T
s
) .........................–60°C to +150°C
Lead Temperature (soldering, 5 sec.)........................ 260°C
EDS Rating
(4)
.................................................................. 2kV
Operating Ratings
(2)
Supply Voltage (V
IN
)........................................ +2.7V to +6V
Enable Voltage (V
EN
).............................................. 0V to V
IN
Junction Temperature (T
J
) ........................ –40°C to +125°C
Thermal Resistance
SOT23-5 (θ
JA
) ..................................................235°C/W
Electrical Characteristics
(5)
V
IN
= V
OUT
+ 1V, V
EN
= V
IN
; I
OUT
= 100µA; T
J
= 25°C,
bold
values indicate –40°C
≤
T
J
≤
+125°C; unless noted.
Symbol
V
O
ΔV
LNR
ΔV
LDR
V
IN
–
V
OUT
I
Q
I
GND
Parameter
Output Voltage Accuracy
Line Regulation
Load Regulation
Condition
I
OUT
= 100µA
V
IN
= V
OUT
+ 1V to 6V
I
OUT
= 0.1mA to 150mA
I
OUT
= 100µA
Dropout Voltage
(7)
I
OUT
= 100mA
I
OUT
= 150mA
V
EN
≤
0.4V (shutdown)
I
OUT
= 0mA
I
OUT
= 150mA
f = 10Hz, V
IN
= V
OUT
+ 1V; C
OUT
= 1.0µF
PSRR
Ripple Rejection
f = 100Hz, V
IN
= V
OUT
+ 0.5V; C
OUT
=
1.0µF
f = 10kHz, V
IN
= V
OUT
+ 0.5V
I
LIM
e
n
V
IL
V
IH
I
EN
Current Limit
Output Voltage Noise
Enable Input Logic-Low Voltage
Enable Input Logic-High
Voltage
Enable Input Current
Shutdown Resistance
Discharge
V
IN
= 2.7V to 5.5V, regulator shutdown
V
IN
= 2.7V to 5.5V, regulator enabled
V
IL
≤
0.4V, regulator shutdown
V
IH
≥
1.6V, regulator enabled
1.6
0.01
0.01
500
V
OUT
= 0V
160
(6)
Min.
–1
–2
Typ.
Max.
1
2
Units
%
%
%/V
%
mV
mV
mV
mV
µA
µA
µA
dB
dB
dB
mV
µV(rms)
0.02
1.5
0.1
90
135
0.2
90
117
60
60
45
425
TBD
0.05
2.5
5
150
200
250
1
150
Quiescent Current
Ground Pin Current
(8)
Enable Input
0.4
V
V
µA
µA
Ω
August 2010
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M9999-080510
Micrel, Inc.
MIC5256
Electrical Characteristics
(5)
(Continued)
V
IN
= V
OUT
+ 1V, V
EN
= V
IN
; I
OUT
= 100µA; T
J
= 25°C,
bold
values indicate –40°C
≤
T
J
≤
+125°C; unless noted.
Symbol
Error Flag
V
FLG
V
OL
I
FL
Low Threshold
High Threshold
Output Logic-Low Voltage
Flag Leakage Current
Thermal-Shutdown
Temperature
Thermal-Shutdown Hysteresis
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
A
(ambient temperature) is P
D(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
θ
JA
of the MIC5255-x.xBM5 (all versions) is
235°C/W on a PC board (see “Thermal Considerations” section for further details).
4. Devices are ESD sensitive. Handling precautions recommended.
5. Specification for packaged product only.
6. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range from
0.1mA to 150mA. 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 1Vdifferential.
For outputs below 2.7V, dropout voltage is the input-to-output voltage differential with the minimum input voltage 2.7V. Minimum input operating
voltage is 2.7V.
8. 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.
Parameter
Condition
% of V
OUT
(Flag ON)
% of V
OUT
(Flag OFF)
I
L
= 100µA, fault condition
flag off, V
FLG
= 6V
Min.
90
Typ.
Max.
Units
%
%
V
µA
96
0.02
0.01
0.1
Thermal Protection
150
10
°C
°C
Test Circuit
August 2010
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M9999-080510
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