LM317MDCYR

Adjustable Positive-Voltage Regulator

The LM317MDCYR is a adjustable positive-voltage regulator from Texas Instruments. View the full LM317MDCYR datasheet below including electrical characteristics, absolute maximum ratings.

Manufacturer

Texas Instruments

Overview

Part: LM317M, LM317MQ — Texas Instruments

Type: Adjustable Positive-Voltage Regulator

Description: Adjustable three-pin, positive-voltage regulators capable of supplying an output current of 0.5A over an output voltage range of 1.25V to 37V, featuring built-in short-circuit current limiting and thermal protection.

Operating Conditions:

Input-to-output differential voltage: 2.5–37 V
Output voltage: 1.25–37 V
Output current: 0.01–0.5 A
Operating junction temperature: -40 to 125 °C

Absolute Maximum Ratings:

Max input-to-output differential voltage: 40 V
Max junction temperature: 150 °C
Max storage temperature: 150 °C

Key Specs:

Line regulation: 0.01 %/V (typ, V_I - V_O = 3V to 40V, T_J = 25°C)
Load regulation: 0.1 % (typ, I_O = 10mA to 500mA, T_J = 25°C, New chip)
ADJUST terminal current: 45 μA (typ, New chip)
Reference voltage: 1.25 V (typ, V_I - V_O = 3V to 40V, I_O = 10mA to 500mA)
Minimum load current to maintain regulation: 2 mA (typ, New chip)
Maximum output current: 500 mA (min, V_I - V_O ≤ 15V, New chip)
RMS output noise voltage: 0.003 %V_O (typ, f = 10Hz to 10kHz, T_J = 25°C)
Ripple rejection: 80 dB (typ, V_O = 10 V, f = 120Hz, C_ADJ = 10μF)

Features:

Adjustable output voltage range (VOUT): 1.25V to 37V
Output current (I OUT): Up to 500mA
Built-in, short-circuit current limiting and thermal protection
Stable without any output capacitor
Floating regulator design
Safe operating area protection

Applications:

Cordless vacuum cleaners
Building security gateways
Multifunction printers
Onboard charging

Package:

SOT-223 (4-pin, 6.5mm × 7mm)
TO-252 (3-pin, 6.6mm × 10.11mm)

Features

Adjustable output voltage range (VOUT): 1.25V to 37V
Output current (I OUT): Up to 500mA
Built-in, short-circuit current limiting and thermal protection
Stable without any output capacitor
Operating temperature range: -40°C to +125°C
Packages:
4-pin, 6.5mm × 7mm SOT-223 (RθJA : 77.7°C/W)
3-pin, 6.6mm × 10.11mm TO-252 (RθJA : 31.7°C/W)

Applications

Pin Configuration

Figure 4-1. DCY Package, 3-Pin SOT-223 (Top View)

Figure 4-2. KVU Package, 3-Pin TO-252 (Top View)

Table 4-1. Pin Functions

PIN	PIN	TYPE	DESCRIPTION
NAME	NO.	TYPE	DESCRIPTION
ADJUST	1	I	Output feedback voltage
OUTPUT	2	O	Regulated output voltage. Use the recommended capacitor value as listed in the Recommended Operating Conditions table. Place the output capacitor as close to the OUTPUT and COMMON pins of the device as possible.
INPUT	3	-	Input supply voltage, 2.5V to 40V relative to OUTPUT pin. Use the recommended capacitor value as listed in the Recommended Operating Conditions table. Place the input capacitor as close to the INPUT and COMMON pins of the device as possible.

Electrical Characteristics

over recommended operating virtual-junction temperature range TJ = -40°C to 125°C, VI - VO = 5 V, IO = 0.1 A (unless otherwise noted)

PARAMETER	TEST CONDITIONS	TEST CONDITIONS	TEST CONDITIONS	MIN	TYP	MAX	UNIT
Line regulation	V I - V O = 3V to 40V	T J = 25°C	Legacy chip and new chip		0.01	0.04	%/V
	V I - V O = 3V to 40V	Legacy chip and new chip	Legacy chip and new chip		0.02	0.07	%/V
Load regulation	I O = 10mA to 500mA	T = 25°C	Legacy chip		0.1	0.5	%
Load regulation	I O = 10mA to 500mA	J	New chip		0.1	0.24	%
Load regulation	I O = 10mA to 500mA	Legacy chip	Legacy chip		0.3	1.5	%
Load regulation	I O = 10mA to 500mA	New chip	New chip		0.1	0.8	%
ADJUST terminal current			Legacy chip		50	100	μA
ADJUST terminal current			New chip		45	65	μA
Change in ADJUST terminal current	V I - V O = 3V to 40V, I O = 10mA to 500mA	V I - V O = 3V to 40V, I O = 10mA to 500mA	Legacy chip		0.2	5	μA
Change in ADJUST terminal current	V I - V O = 3V to 15V, I O = 10mA to 500mA V I - V O = 15V to 40V, I O = 100mA	V I - V O = 3V to 15V, I O = 10mA to 500mA V I - V O = 15V to 40V, I O = 100mA	New chip		0.2	5	μA
Reference voltage	V I - V O = 3V to 40V, I O = 10mA to 500mA	V I - V O = 3V to 40V, I O = 10mA to 500mA	Legacy chip	1.2	1.25	1.3	V
Reference voltage	V I - V O = 3V to 15V, I O = 10mA to 500mA V I - V O = 15V to 40V, I O = 100mA	V I - V O = 3V to 15V, I O = 10mA to 500mA V I - V O = 15V to 40V, I O = 100mA	New chip	1.2	1.25	1.3	V
Minimum load current to maintain regulation			Legacy chip		3.5	10	mA
Minimum load current to maintain regulation			New chip	1.1	2	3.5	mA
Output-voltage temperature stability			Legacy chip and new chip		0.7		%
Maximum output current			Legacy chip	500	900		mA
Maximum output current	V I - V O ≤ 15V	V I - V O ≤ 15V	New chip	500	1000	1600	mA
	V I - V O = 40V, PD ≤ PD(max) (1)	T J = 25°C	Legacy chip	150	250
	V I - V O = 40V, PD ≤ PD(max) (1)	T J = 25°C	New chip	110	220	350
RMS output noise voltage (% of VO)	f = 10Hz to 10kHz,	T J = 25°C	Legacy chip and new chip		0.003		%V O
Long-term stability		T J = 25°C	Legacy chip		0.3	1	%/1k
Long-term stability	I O =10mA	T J = 25°C	New chip		0.3	1	hrs
Ripple rejection	V O = 10 V, f = 120Hz, C ADJ = 0	T J = 25°C	Legacy chip		65		dB
Ripple rejection		T J = 25°C	New chip		65		dB
Ripple rejection	V O = 10 V, f = 120Hz, C ADJ = 10μF	T J = 25°C	Legacy chip	66	80
Ripple rejection	V O = 10 V, f = 120Hz, C ADJ = 10μF		New chip	66	80

Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)

		MIN	MAX	UNIT
Vi - Vo	Input-to-output differential voltage		40	V
T J	Operating junction temperature		150	°C
T stg	Storage temperature	-65	150	°C

Recommended Operating Conditions

over operating junction temperature range (unless otherwise noted)

		MIN	NOM	MAX	UNIT
V I - V O	Input-to-output differential voltage	2.5		37	V
V O	Output voltage	1.25		37	V
I O	Output current	0.01		0.5	A
C IN	Input capacitor		0.1		μF
C OUT (1)	Output capacitor		0.1		μF
ESR (1)	Output capacitor	0.01		2	Ω
T J	Operating junction temperature	-40		125	°C

Thermal Information

		LM317M, LM317MQ	LM317M, LM317MQ	LM317M, LM317MQ	LM317M, LM317MQ
THERMAL METRIC (1)	THERMAL METRIC (1)	DCY (Legacy Chip)	DCY (New Chip)	KVU (Legacy Chip)	KVU (New Chip)
		3 PINS	3 PINS	3 PINS	3 PINS
R θJA	Junction-to-ambient thermal resistance	60.2	77.7	34.8	31.7
R θJC(top)	Junction-to-case (top) thermal resistance	42	44.6	46.3	39.4
R θJB	Junction-to-board thermal resistance	9.4	15.1	15.6	10.1
Ψ JT	Junction-to-top characterization parameter	3.4	5.3	6.9	3.8
Ψ JB	Junction-to-board characterization parameter	9.3	14.7	15.6	10.1
R θJC(bot)	Junction-to-case (bottom) thermal resistance	n/a	n/a	6.2	3

Typical Application

The LM317M and LM317MQ are linear voltage regulators. The feedback is the output pin to adjust pin differential. Set the output voltage to any value from 1.25V to V O maximum with two resistors.

Package Information

PART NUMBER	PACKAGE (1)	PACKAGE SIZE (2)
LM317M, LM317MQ	DCY (SOT-223, 3)	6.5mm × 7mm
LM317M, LM317MQ	KVU (TO-252, 3)	6.6mm × 10.11mm

(1) For more information, see the Mechanical, Packaging, and Orderable Information .
(2) The package size (length × width) is a nominal value and includes pins, where applicable.

Typical Application Circuit

Related Variants

The following components are covered by the same datasheet.

Part Number	Manufacturer	Package
LM317	Texas Instruments	TO-220-3
LM317M	Texas Instruments	—
LM317MDCY	Texas Instruments	—
LM317MDCY.A	Texas Instruments	—
LM317MDCYR.A	Texas Instruments	—
LM317MDT-TR	Texas Instruments	TO-252-2(DPAK)
LM317MQ	Texas Instruments	—

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