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Details, datasheet, quote on part number:LM317S
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Datasheet text preview:
Bay Linear
Inspire the Linear Power
3-Terminal 1.5Amp Adjustable Voltage Regulator Description
The Bay Linear LM317 are monolithic integrated circuit in TO- 220, TO-252, SOT-223 and D2PAK packages intended for use as positive adjustable voltage regulators. They are designed to supply more than 1.5A of load current with an output voltage adjustable over a 1.2 to 37V range. The nominal output voltage is selected by means of only a resistive divider, making the device exceptionally easy to use and eliminating the stocking of many fixed regulators.
LM317
Features
· · · · · · · · Output Current of 1.5A Output Voltage Tolerance of 5% Adjustable Output 1.2V to 37V 0.1% Load & Line Regulation Internal Short-Circuit Limited Current Limit Offer in plastic TO-252, TO-220, SOT-223 & TO-263 Direct Replacement for LM317
Applications
· · Post regulator for switching DC/DC converter Bias supply for analog circuits
Packaging Information
Ordering Information
Device
LM317T LM317N LM317S LM317D
TO-263-3 (S) (
Package Type
TO-220 SOT-223 TO-263 TO-252
Output
1.5 Amp 1.0 Amp 1.5 Amp 1.5 Amp
Bay Linear
1 2 3
1. ADJ 2. Output 3. Input
SOT-223 Vs. TO-252 Package
Top Top View
Bay Linear, Inc
2418 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
LM317
Absolute Maximum Rating
Parameter
Power Dissipation Input Voltage Differential Operating Free-Air, Case, Virtual Junction Temp. Storage Temperature Range Lead temperature 1.6 mm from case for sec.
LM317
Internally Limited +40V, -0.3V 0 to 150 -65 to 150 260
Unit
V °C
Electrical Characteristics (LM317)
Parameter
Reference Voltage Line Regulation Load Regulation Ripple Rejection
Symbol
VO VO VO RR
Conditions
3V(VIN-VOUT) 40V 10mAIOUTIMAX, PPMAX 3V(VIN-VOUT) 40V (Note 4) 10mAIOUT IMAX (Note 4) VI = 10V,, f=120Hz CADJ=0µF VI = 10V,, f=120Hz CADJ=10µF 20ms
MIN
1.20
TYP
1.25 0.01 0.02 0.1 0.3 65
MAX
1.30 0.02 0.05 0.3 1
UNIT
V %/V % % dB dB
66
80 0.03 50 0.2 1 0.3 0.003 3.5 0.07 100 5
Thermal Regulation Adjustment Pin Current Adjustment Pin Current Change Temperature Stability Long Term Stability RMS Output Noise % of VOUT Minimum Load Current Maximum Load Current
%W µA µA % % % mA A A
10mAIOUTIMAX, 3V(VIN-VOUT) 40V TMINTJTMAX TJ=125°C, 1000 hrs 10Hzf10KHz (VIN-VOUT) =40V (VIN-VOUT) 15V PDPMAX (VIN-VOUT) 40V PDPMAX 1.5
1
5
2.2 0.4
Bay Linear, Inc
2418 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
LM317
Application Notes:
The LM317 provides an internal reference voltage of 1.25V between the output and adjustments terminals. This is used to set a constant current flow across an external resistor divider show below, giving an output voltage VO of: VO = VREF ( 1 + R 2 R 1 ) + IADJ R2 The device was designed to minimize the term IADJ ( 100 m A max) and to maintain it very constant with line and load changes. Usually, the error term IADJ V R2 can be neglected. To obtain the previous requirement, all the regulator quiescent current is returned to the output terminal, imposing a minimum load current condition. If the load is insufficient, the output voltage will rise. Since the LM317 is a floating regulator and " sees" only the input- tooutput differential voltage, supplies of very high voltage with respect to ground can be regulated as long as the maximum input- to- output differential is not exceeded. Furthermore, programmable regulator are easily obtainable and, by connecting a fixed resistor between the adjustment and output, the device can be used as a precision current regulator. In order to optimise the load regulation, the current set resistor R1 show below should be tied as close as possible to the regulator, while the ground terminal of R2 should be near the ground of the load to provide remote ground sensing. Performance may be improved with added capacitance as follow: An input bypass capacitor of 0.1µF An adjustment terminal to ground 10µF capacitor to improve the ripple rejection of about 15 dB ( CADJ). An 1µF tantalium ( or 25 µFAluminium electrolitic) capacitor on the output to improve transient response. In additional to external capacitors, it is good practice to add protection diodes, as shown in below. D1 protect the device against input short circuit, while D2 protect against output short circuit for capacitance discharging.
Bay Linear, Inc
2418 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
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