MICROSEMI LX8211A

LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
KEY FEATURES
DESCRIPTION
ƒ Dropout Voltage Typically
140mV @ 100mA
ƒ Ultra Low Shutdown Current
Typically Less Than 1µA
ƒ High Output Accuracy Trimmed
to 0.25%
ƒ Standard Pinout in SOT-23-5
ƒ Current and Over Temperature
Protection
ƒ Stable With Low Cost Ceramic
Output Capacitor
The PNP output transistor allows for
ultra low dropout typically less than
140mV at 100mA.
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The LX8211A adjustable voltage
linear regulator combines low dropout,
high accuracy, very low ground current
and fast response in a very small
footprint.
Using the Enable pin the regulator is
switched on with TTL logic levels,
which is especially useful for batteryoperated equipment.
Other features
include independent thermal and short
circuit current protection. The regulator
is stable with a low value ceramic output
capacitor.
APPLICATIONS
ƒ
ƒ
ƒ
ƒ
ƒ
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
Battery Operated Systems
Laptop, Notebook and PDA’s
Cellular Telephones / Pagers
Hand-Held Instruments
Linear post Regulators for
SMPS
PRODUCT HIGHLIGHT
⎛ R2 ⎞ + ⎛
⎞
VOUT = VADJ ⎜1+
IADJ R2⎟
⎟
⎜
⎝ R1 ⎠ ⎝
⎠
1
VIN
ON
3
+
¯
OFF
VOUT
Part
4
CBYP
470pF
GND
LX8211A
COUT
10µF
R1
ENABLE
ADJUST
CIN
1µF
5
2
R2
CBYP Optional for low noise
LX8211A
TJ (°C)
PACKAGE ORDER INFO
Plastic SOT-23
SE 5-PIN
OUTPUT VOLTAGE
PACKAGE MARKING
RoHS Compliant / Pb-free
-40 to 125
Adjustable
LX8211A-00ISE
E2C
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX8211A-25ISE-TR)
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
PACKAGE PIN OUT
Input Voltage (VIN) ...................................................................................... -0.3V to +15V
Enable Input ........................................................................................-0.3V to VIN + 0.3V
Output Current (IOUT) ............................................................................................. 150mA
Maximum Junction Temperature (TJ) ....................................................................... 150°C
Peak Package Solder Reflow Temperature (40 second max. exposure)....... 260°C (+0, -5)
Note:
Exceeding these ratings could cause damage to the device. All voltages are with respect to
Ground. Currents are positive into negative out of specified terminal.
1
5
2
4
3
SE PACKAGE
(Top View)
RoHS / Pb-free 100% Matte Tin Lead Finish
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ABSOLUTE MAXIMUM RATINGS
THERMAL DATA
SE
5-PIN SOT-23 PACKAGE
Thermal Resistance – Junction to Ambient, θJA
„
„
220°C/W
220°C/W
Two – Layer Board
Four – Layer Board
Junction Temperature Calculation: TJ = TA + (PD x θJA).
The θJA numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.
FUNCTIONAL PIN DESCRIPTION
PIN NAME
PIN
NUMBER
VIN
1
DESCRIPTION
Unregulated Input Supply Voltage
GND
2
Ground Pin
ENABLE
3
Enable Control Input, Enable High
ADJUST
4
Adjust Control Input for Resistor Divider Network.
VOUT
5
Regulated Output Voltage. Regulator stability is achieved with an external capacitor of 10µF.
PACKAGE DATA
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
Parameter
Symbol
Input Operating Voltage Range (Note 1)
Minimum Output Voltage
Enable Input Voltage Range
Continuous Output Current Range
Operating Temperature Range
Input Capacitor (VIN to GND)
Output Capacitor (VOUT to GND)
VIN
Min
LX8211A
Typ
Units
Max
3.0
13.0
V
2.3
V
ENABLE
0
VIN
IOUT
TJ
CIN
COUT
0.1
150
125
-40
1.0
10
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RECOMMENDED OPERATING CONDITIONS
mA
°C
µF
µF
1.0*
Note 1: The minimum VIN has to meet two conditions VIN > 3.0V and VIN > VOUT + VDROPOUT.
* Size your output capacitor to meet the transient loading requirement. If you have a very dynamic load, a lower ESR and larger value capacitor will
improve the response to these load steps.
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, the following specifications apply over the operating ambient temperature -40°C ≤ TJ ≤ 125°C except where
noted. Test conditions: VIN = VOUT+1V, VOUT = 2.9V; IOUT = 10mA; CIN = 1µF; COUT = 10µF; TJ = TA, using low duty cycle pulse testing
methods.
Parameter
Symbol
LX8211A
Test Conditions
Units
Min
Typ
Max
1.225
1.25
1.275
V
Adjust Reference Voltage
VADJ
Note 3
ΔV
⎞
Line Regulation ⎛⎜ O
ΔVIN ⎟⎠
⎝
VRV
VIN = VOUT + 1.0 TO 13 Volts, IOUT=0.1mA
0.04
0.1
%/V
ΔV
⎞
Load Regulation ⎛⎜ O
ΔIO ⎟⎠
⎝
VRI
TJ = 25°C, IOUT: 0.5 TO 150mA
0.05
Dropout Voltage (VIN − VO )
VDO
(Note2)
0.2
%VNOM
IOUT: 0.5 TO 150mA
0.5
%VNOM
ILOAD = 10mA, ΔVO = -1%
0.1
V
0.23
V
ILOAD = 50mA, ΔVO = -1%
0.12
0.175
0.3
V
0.25
0.35
V
Enable = Hi, IOUT = 100mA
600
1500
µA
Enable = Hi, IOUT = 150mA
1300
2500
µA
5
µA
50
500
nA
25
µA
Ground Pin Current
IGND
Adjust Input Bias Current
IADJ
Current Flows Out of Pin 4
Enable Pin Current
IEN
VEN = VIN
Enable = Low (Standby)
VIH
Enable Threshold
2.0
V
0.18
VIL
Short Circuit Current Limit
IOUTSC
Power Supply Rejection Ratio
PSRR
Output Noise
eN
Thermal Shutdown Temperature
TSD
VOUT = 0V
400
V
mA
TJ = 25°C, f = 120Hz
75
dB
TJ = 25°C, COUT = 10µF
260
nv /√Hz
170
°C
Note 2: Dropout voltage is defined as the input to output differential at which the output voltage drops 1% below the nominal value.
Note 3: Limits require operation within recommended operating conditions.
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
ELECTRICALS
ILOAD = 100mA, ΔVO = -1%
ILOAD = 150mA, ΔVO = -1%
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
VIN
VOUT
Thermal
Shutdown
ADJUST
+
Current
Limit
ENABLE
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BLOCK DIAGRAM
Control
Logic
-
VREF
GND
LX8211A
Figure 1 – Simplified Adjustable Version Block Diagram
BLOCK DIAGRAM
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
2.915
1.252
2.91
V ADJUST, Volts
V ADJUST, Volts
1.25
1.248
1.246
1.244
2.905
2.9
2.895
2.89
1.242
2.885
1.24
2.88
-50
1.238
-50
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TYPICAL CHARACTERISTICS
Typical performance characteristics, unless otherwise specified are: CIN = 1µF, COUT = 10µF, CBY = 470pF, VIN = 4V, VOUT = 2.9V,
TA = 25°C, ENABLE is tied to VIN.
VOUT (Programmed to 2.9V) vs. TEMPERATURE
V ADJUST vs. TEMPERATURE
-25
0
25
50
75
100
125
-25
0
25
50
75
100
125
150
TEMPERATURE, °C
150
TEMPERATURE, °C
DROPOUT VOLTAGE (Vin=3.9V)
SHORT CIRCUIT CURRENT vs. TEMP and VIN
550
150mA
100mA
10mA
250
VIN=13V
VIN=3.9V
525
500
200
CURRENT, mA
DROPOUT VOLTAGE, mV
300
150
100
475
450
425
400
375
350
50
325
300
0
-50
-25
0
25
50
75
100
125
-50
150
-25
0
25
50
75
100
125
150
TEMPERATURE, °C
TEMPERATURE, °C
LINE and LOAD REGULATION
GROUND CURRENT vs IOUT (Vin=3.9V)
2.25
0.30
150mA
100mA
10mA
2.00
0.25
VOUT, % CHANGE
CURRENT, mA
1.75
1.50
1.25
1.00
0.75
0.50
0.20
0.15
LINE (3.9-13v)
0.10
LOAD(0.5MA-150MA)
0.05
0.25
-50
-25
0
25
50
75
100
125
150
TEMPERATURE, °C
Copyright © 2006
Rev. 1.0, 2006-04-07
-50
-25
0
25
50
75
100
125
150
TEMPERATURE, °C
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
CHARTS
0.00
0
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
WWW . Microsemi .C OM
TYPICAL CHARACTERISTICS (CONTINUED)
Typical performance characteristics, unless otherwise specified are: CIN = 1µF, COUT = 10µF, CBY = 470pF, VIN = 4V, VOUT = 2.9V,
TA = 25°C, ENABLE is tied to VIN.
Power Supply Rejection vs. Frequency
10MA LOAD CBYPASS = 470PF
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
100
1K
10K
Enable Response
VIN = 4V, CIN = 1µF, COUT = 10µF, CBYP = 470pF, IOUT = 100mA.
CH2 = VOUT = 2.9V. CH1 - VENABLE
VIN = 4V, CIN = 1µF, COUT = 10µF, CBYP = 470pF, IOUT = 100mA.
CH2 = VOUT = 2.9V. CH1 = VIN from 3.5V to 4.5V
Load Transient Response
VIN = 4V, CIN = 1µF, COUT = 10µF, CBYP = 470pF, IOUT = 50mA.
CH2 = VOUT = 2.9V. CH4 = ISTEP = 20mA to 70mA
100K
Line Regulation Step Response
Load Transient Response
VIN = 4V, CIN = 1µF, COUT = 10µF, CBYP = 470pF, STEP Load = 100mA.
CH2 = VOUT = 2.9V. CH4 = ISTEP = 20mA to 100mA
CHARTS
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
Description
Minimum Load Requirement
The LX8211A is a family of LDO (Low Dropout) linear regulators in
a small SOT-23 Package, which provides a compact and cost effective
solution. The family includes several fixed output voltages, along with
an adjustable version. The internal PNP power device provides low
dropout regulation with fast line and load transient response. It also
includes internal current limit and thermal shutdown circuitry. This
section contains information about the selection of external capacitors,
thermal, and layout consideration.
The LX8211A is stable even at zero load; no minimum load is required
for operation, which is especially important in keep-alive applications.
However line regulation is improved with a minimum load of 100µA.
Input Capacitor
Short Circuit Current Protection
To improve load transient response and noise rejection a bypass
capacitor is recommended, but it is not required for stability. There are
no requirements for the ESR (Equivalent Series Resistor) on the input
capacitor, but tolerance and temperature coefficient must be
considered when selecting the capacitor to ensure the capacitor will be
around 1µF over the entire operating temperature range. For the
LX8211A connect a ceramic type capacitor (1µF) between VIN and
ground.
The LX8211A includes over current protection, when the output load
current exceeds typically 400mA the circuit forces the regulator to
decrease in output.
Output Capacitor
To maintain a constant output voltage a feedback loop is necessary.
The feedback loop causes a well known a phase shift, the amount of
phase shift determines the loop stability. Therefore the LX8211A, like
any low dropout regulator, requires an output capacitor with low ESR
(Equivalent Series Resistor) connected between VOUT and GND to
stabilize the internal control loop. For the LX8211A a ceramic,
tantalum, or electrolytic capacitor with the minimum recommended
capacitance value at 10µF with ESR between 5mΩ and 1Ω will satisfy
the stability for whole operating range.
The LX8211A-00 adjustable regulator’s output voltage can be
externally set by connecting the ADJ pin to an external resistor divider
(See Figure 1). The output voltage can be calculated using:
⎡
⎣
R2 ⎤
+ [I • R2]
R1 ⎥⎦ ADJ
Thermal Consideration
Thermal shutdown protects the integrated circuit from thermal
overload caused from a rise in junction temperature during power
dissipation. This means of protection is intended for fault protection
only and not as a means of current or power limiting during normal
application usage. Proper thermal evaluation should be done to ensure
that the junction temperature does not exceed its maximum rating.
Operating at the maximum TJ of 150°C can impact reliability. Due to
variation in individual device electrical characteristics and thermal
resistance, the built in thermal overload protection may be activated at
power levels slightly above or below the rated dissipation.
Power dissipation for regulator can be calculated using the following
equation:
PD = (VIN(MAX)-VOUT(MIN)) * IOUT(MAX)
For the SOT23 package, thermal resistance, θJA is 220°C/W when
mounted on a FR4 copper clad PCB. Junction temperature of the
integrated circuit can be calculated using:
TJ = TA + TRISE, substituting: TA + (PD * θJA).
An example:
Given conditions: TA = 60°C, VIN= 4.2V, VOUT= 2.7V, IOUT= 100mA.
Enable
Calculated values:
Total Power dissipation PD(total) = (4.2-2.7) V * 0.1A =0.15W
Junction Temperature
TJ = 60°C +(0.15W *220°C/W) = 93°C
Layout Consideration:
The layout must be done with low impedance paths for VIN, VOUT, and
Ground by applying sufficient wide traces to avoid voltage drops and
pick up noise. Adding an area of PCB copper to the GND pin (pin2)
will reduce the overall θJA since it is thermally connected to the device
substrate. This will lower the device junction temperature improving
the overall output accuracy. The input / output capacitors must be
placed as close as possible to the voltage regulator output pin. To allow
the same voltage reference for all circuits, use a star configuration from
the output capacitor to the different loads.
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
APPLICATION
The Enable pin allows the LX8211A to be turned on and off. The
Enable pin is compatible with standard TTL-CMOS levels. A logic
zero (0.4V) on the Enable pin shuts the LX8211A off and reduces the
supply current to less than 1µA. Pulling the Enable input high (2.0V)
causes normal operation to resume. If the Enable feature is not used,
this pin can be connected to VIN.
Copyright © 2006
Rev. 1.0, 2006-04-07
Thermal protection shuts the LX8211A down when the junction
temperature exceeds approximately 150°C; there is no appreciable
thermal hysteresis.
(Note: power dissipation resulting from quiescent current is negligible)
Adjustable Output Voltage
VOUT = 1.25⎢1 +
Temperature Protection
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APPLICATION INFORMATION
LX8211A
®
TM
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
SE
WWW . Microsemi .C OM
PACKAGE DIMENSION
5 Pin Plastic SOT-23
D
Dim
G
H
E
A1
A
C
B
F
J
I
A
A1
B
C
D
E
F
G
H
I
J
K
MILLIMETERS
MIN
MAX
0.90
1.30
0.90
1.45
0.25
0.50
0.09
0.20
2.80
3.10
1.50
1.75
0.95 BSC
1.90 BSC
2.60
3.00
0.35
0.55
0.00
0.15
10° MAX
INCHES
MIN
MAX
0.035
0.051
0.035
0.057
0.010
0.020
0.004
0.008
0.110
0.122
0.059
0.069
0.038 BSC
0.075 BSC
0.102
0.118
0.014
0.022
0.000
0.006
10° MAX
K
Note:
1. Dimensions do not include mold flash or protrusions;
these shall not exceed 0.155mm(.006”) on any side.
Lead dimension shall not include solder coverage.
MECHANICALS
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
LX8211A
TM
®
150mA Low Dropout Regulator
P RODUCTION D ATA S HEET
WWW . Microsemi .C OM
NOTES
NOTES
PRODUCTION DATA – Information contained in this document is proprietary to
Microsemi and is current as of publication date. This document may not be modified in
any way without the express written consent of Microsemi. Product processing does not
necessarily include testing of all parameters. Microsemi reserves the right to change the
configuration and performance of the product and to discontinue product at any time.
Copyright © 2006
Rev. 1.0, 2006-04-07
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9