LX8941
TM ®
Adjustable Low Dropout Regulator
P RODUCTION D ATA S HEET
DESCRIPTION
KEY FEATURES
The Microsemi LX8941 is an adjustable, low dropout regulator rated for more than 1A of output current. It can regulate with as low as 0.8V headroom between the input and output voltages, at 1A output current, thus minimizing power dissipation. In addition, it can be used in applications where worst case supplies require a low input / output differential to maintain regulation.
This feature makes it ideal for some processor applications that require 4V operation from a 5V supply. In addition, the LX8941 provides an on / off switch that reduces the IC quiescent current when activated, making it ideal for battery operated applications.
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
2% Internally Trimmed Output Output Current In Excess of 1A Input – Output Differential Less Than 0.8V @ 1A Reverse Battery Protection Short Circuit Protection Internal Thermal Overload Protection Available in 5-Lead Plastic TO-220 & Surface-Mount TO-263
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PRODUCT HIGHLIGHT
Dropout Voltage vs. Output Current vs. Temperature
5V 10 µF
ON OFF R2 187
IN
Dropout Voltage - (mV)
Part LX8941
OUT
R1 412
4V
600 500 400 300 200 100 0 100 500 1000 Output Current (mA)
125°C 25°C -40°C
ADJ
22µF
LX8941 LX8941
PACKAGE ORDER INFO
TA (°C) 0 to 70
P
Plastic TO-220 5 pin LX8941CP
DD
Plastic TO-263 5 Pin LX8941CDD
RoHS Compliant / Pb-free Transition DC: 0543
RoHS Compliant / Pb-free Transition DC: 0535
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX8941CDD-TR)
Copyright © 2001 Rev. 1.0, 2011-02-04
Microsemi
Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX8941
TM ®
Adjustable Low Dropout Regulator
P RODUCTION D ATA S HEET
ABSOLUTE MAXIMUM RATINGS Input Voltage (VIN) ....................................................................................................... 26V Operating Temperature Range ................................................................................... 150°C Storage Temperature Range ........................................................................ -65°C to 150°C Lead Temperature (Soldering 10 seconds) ................................................................. 300°C Package Peak Temp. for Solder Reflow (40 seconds maximum 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.
PACKAGE PIN OUT
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TAB is GND
5 4 3 2 1
ON/OFF ADJ GND VO VIN
P PACKAGE
(Top View)
TAB is GND
5 4
ON/OFF ADJ GND VO VIN
THERMAL DATA
3 2
P
Plastic TO-220 5-Pin 4.5°C/W 60°C/W
1
THERMAL RESISTANCE-JUNCTION TO TAB, θJT
DD PACKAGE
(Top View)
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
RoHS / Pb-free 100% matte Tin Lead Finish
DD
Plastic TO-263 5-Pin 4.5°C/W 60°C/W
THERMAL RESISTANCE-JUNCTION TO CASE, θJC
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
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.
RECOMMENDED OPERATING CONDITIONS Parameter Input Voltage Load Current (with Adequate Heat sinking) Input Capacitor (VIN to GND) Output Capacitor with ESR of min 0.1Ω, 10Ω max*., (VO to GND) Symbol VIN IL LX8941 Typ Units V mA µF µF
Min 3.8 5 0.1 10
Max 26 1000
* At low output current levels the range of acceptable ESR values may be narrower, and should be evaluated to insure stability
P D PACKAGE DATA
Copyright © 2001 Rev. 1.0, 2011-02-04
Microsemi
Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LX8941
TM ®
Adjustable Low Dropout Regulator
P RODUCTION D ATA S HEET
ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following characteristics apply over the operating ambient temperature of 0°C to 125°C for the LX8941CP & LX8941CDD; VIN = 10V, IO = 1A, COUT = 22µF and are for DC characteristics only. Low duty cycle pulse testing techniques are used which maintain junction and case temperatures equal to the ambient temperature. Note 2: The output voltage range is 4V to 25V and is determined by the two external resistors, R1 and R2. See Product Highlight.
Parameter ADJ Pin Voltage (Note 2) Line Regulation Load Regulation Dropout Voltage Quiescent Current Adjust Pin Current Current Limit Output Noise Voltage (Note 3) Long Term Stability (Note 3) Ripple Rejection (Note 3) Enable Logic Section On Threshold Voltage On Threshold Current Off Threshold Voltage Off Threshold Current RR fO = 120Hz, 1VRMS, IO = 100mA 2 0.1 -10 -0.3 50 0.8 Symbol VADJ ∆VOI ∆VOL ∆V IQ IADJ ICL VO RMS Test Conditions IO = 0A, TA = 25°C VO + 2V < VIN < 26V, IO = 5mA 50mA < IO < 1A, VO = VADJ IO = 100mA IO = 500mA IO = 1A IO = < 5mA, 7 < VIN < 26V IO = 500mA IO = 1000mA VIN = 10V, IO = 1A VIN = 26V 10Hz – 100kHz, IO = 5mA LX8941 Typ 1.25 1 10 150 275 400 3 30 115 2 1.2 150 20 66 Units V mV mV mV mV mV mA mA mA µA A µVRMS mV / 1000hr dB V µA V µA
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Min 1.225
Max 1.275 50 50 300 500 800 15 50 180 20
1
Note 3: These parameters although guaranteed, are not tested in production.
SIMPLIFIED BLOCK DIAGRAM
INPUT VOLTAGE
C1* 0.1µF
VIN
LX8941
VO
C2 10µF
OUTPUT VOLTAGE
Thermal Shutdown +
ADJ
ELECTRICALS
ON / OFF
ON OFF
ON / OFF Circuit
GND
Figure 1 – Simplified Block Diagram
Copyright © 2001 Rev. 1.0, 2011-02-04
Microsemi
Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
LX8941
TM ®
Adjustable Low Dropout Regulator
P RODUCTION D ATA S HEET
PACKAGE DIMENSIONS
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DD
5-Pin Plastic TO-263
A I D
C
B K M N
H F G E
Dim A B C D E F G H I J K M N
MILLIMETERS MIN MAX 10.03 10.67 8.51 9.17 4.19 4.59 1.14 1.40 0.330 0.51 0.74 0.89 1.57 1.83 2.29 2.79 – 1.65 0 0.25 14.60 15.87 7° 3°
INCHES MIN MAX 0.395 0.420 0.335 0.361 0.165 0.181 0.045 0.055 0.013 0.020 0.029 0.035 0.062 0.072 0.090 0.110 – 0.065 0 0.010 0.575 0.625 7° 3°
0° -8°
J Seating Plane
P
5-Pin Plastic TO-220
B S F T
A
1
5 R
C
K D
Dim A B C D F G J K N R S T
Note:
MILLIMETERS MIN MAX 14.23 16.51 9.66 10.66 3.56 4.82 0.46 0.89 3.56 4.06 3.40 0.31 1.14 12.70 14.73 6.80 TYP 2.04 2.92 1.14 1.39 5.85 6.85
INCHES MIN MAX 0.560 0.650 0.380 0.420 0.140 0.190 0.018 0.035 0.140 0.160 0.134 0.012 0.045 0.500 0.580 0.268 TYP 0.080 0.115 0.045 0.055 0.230 0.270
MECHANICALS
J
G N
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.
Copyright © 2001 Rev. 1.0, 2011-02-04
Microsemi
Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
LX8941
TM ®
Adjustable Low Dropout Regulator
P RODUCTION D ATA S HEET
NOTES
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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 © 2001 Rev. 1.0, 2011-02-04
Microsemi
Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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