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
November 2006
1
M9999-111606
Micrel, Inc.
MIC5256
Ordering Information
Part Number
Standard
MIC5256-2.5BM5
MIC5256-2.6BM5
MIC5256-2.7BM5
MIC5256-2.8BM5
MIC5256-2.85BM5
MIC5256-2.9BM5
MIC5256-3.0BM5
MIC5256-3.1BM5
MIC5256-3.3BM5
MIC5256-2.85BD5
Notes:
*
Under bar symbol ( _ ) may not be to scale.
** Other Voltage available. Contact Micrel for details.
Marking
Pb-Free
Standard
LX25
LX26
LX27
LX28
LX2J
LX29
LX30
LX31
LX33
NX2J
Pb-Free*
LX25
LX26
LX27
LX28
LX2J
LX29
LX30
LX31
LX33
NX2J
Voltage**
2.5V
2.6V
2.7V
2.8V
2.85V
2.9V
3.0V
3.1V
3.3V
2.85V
Junction
Temp. Range
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
–40° to +125°C
Package
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin SOT23
5-Pin TSOT23
MIC5256-2.5YM5
MIC5256-2.6YM5
MIC5256-2.7YM5
MIC5256-2.8YM5
MIC5256-2.85YM5
MIC5256-2.9YM5
MIC5256-3.0YM5
MIC5256-3.1YM5
MIC5256-3.3YM5
MIC5256-2.85YD5
Pin Configuration
MIC5256-x.xBM5
5-Pin SOT23
MIC5256-x.xBD5
5-Pin Thin SOT23
MIC5256-x.xYM5
5-Pin SOT23
MIC5256-x.xYD5
5-Pin Thin SOT23
Pin Description
Pin Number
1
2
3
4
5
Pin Name
IN
GND
EN
FLG
OUT
Pin Name
Supply Input.
Ground.
Enable/Shutdown (Input): CMOS compatible input. Logic high = enable;
logic low = shutdown. Do not leave open.
Error Flag (Output): Open-drain output. Active low indicates an output
undervoltage condition.
Regulator Output.
November 2006
2
M9999-111606
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
∆V
LNR
∆V
LDR
V
IN
– V
OUT
Parameter
Output Voltage Accuracy
Line Regulation
Load Regulation
Dropout Voltage
(7)
Condition
I
OUT
= 100µA
V
IN
= V
OUT
+ 1V to 6V
I
OUT
= 0.1mA to 150mA
(6)
I
OUT
= 100µA
I
OUT
= 100mA
I
OUT
= 150mA
I
Q
I
GND
PSRR
Quiescent Current
Ground Pin Current
(8)
Ripple Rejection
V
EN
≤
0.4V (shutdown)
I
OUT
= 0mA
I
OUT
= 150mA
f = 10Hz, V
IN
= V
OUT
+ 1V; C
OUT
= 1.0µF
f = 100Hz, V
IN
= V
OUT
+ 0.5V; C
OUT
= 1.0µF
f = 10kHz, V
IN
= V
OUT
+ 0.5V
I
LIM
e
n
Enable Input
V
IL
V
IH
I
EN
Enable Input Logic-Low Voltage
Enable Input Logic-High Voltage
Enable Input Current
Shutdown Resistance Discharge
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
% of V
OUT
(Flag ON)
% of V
OUT
(Flag OFF)
I
L
= 100µA, fault condition
flag off, V
FLG
= 6V
90
96
0.02
0.01
150
10
0.1
%
%
V
µA
°C
°C
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
0.4
V
V
µA
µA
Ω
Current Limit
Output Voltage Noise
V
OUT
= 0V
160
Min
–1
–2
0.02
1.5
0.1
90
135
0.2
90
117
60
60
45
425
tbd
Typ
Max
1
2
0.05
2.5
5
150
200
250
1
150
Units
%
%
%/V
%
mV
mV
mV
mV
µA
µA
µA
dB
dB
dB
mV
µV(rms)
Thermal Protection
November 2006
3
M9999-111606
Micrel, Inc.
MIC5256
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.
Test Circuit
November 2006
4
M9999-111606
Micrel, Inc.
MIC5256
Typical Characteristics
130
GROUND CURRENT (µA)
125
120
115
110
105
100
0.1
Ground Pin Current
V
IN
= V
OUT
+ 1V
1
10
100
1000
OUTPUT CURRENT (mA)
140
GROUND CURRENT (µA)
120
100
80
60
40
20
Ground Pin Current
OUTPUT VOLTAGE (V)
3.5
Dropout Characteristics
3 I
LOAD
= 100µA
2.5
2
1.5
1
0.5
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
INPUT VOLTAGE (V)
I
LOAD
= 150mA
0
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
INPUT VOLTAGE (V)
I
LOAD
= 150mA
180
DROPOUT VOLTAGE (mV)
160
140
120
100
80
60
40
20
Dropout Voltage
DROPOUT VOLTAGE (mV)
180
160
140
120
100
80
60
40
20
Dropout Voltage
T = –40C
T = 25C
T = 125C
I
0
-40 -20 0 20 40 60 80 100120140
TEMPERATURE ( C)
°
LOAD
= 150mA
0
0 20 40 60 80 100 120 140 160
OUTPUT CURRENT (mA)
November 2006
5
M9999-111606
京公网安备 11010802033920号
EEWORLD
