•
LND317
DATA
SHEET
GENERAL DESCRIPTION
• Output Voltage Range Adjustable
from 1.2V to 37V
• Output Current Capability of 1.5A Max
• Input Regulation Typically 0.01% per
Input-Volt Change
• Output Regulation Typically 0.1%
• Peak Output Current Constant Over
Temperature Range of Regulator
• Popular 3-Lead TO-220 Package
• Ripple Rejection Typically 80 dB
• Direct Replacement for National
LM317
FEATURES
The LND317 is an adjustable 3-terminal positive-
voltage regulator capable of supplying 1.5A over a
differential voltage range of 3V to 40V. It is
exceptionally easy to use and requires only two
external resistors to set the output voltage. Both
input and output regulation is better than standard
fixed regulators.
In addition to higher performance than fixed
regulators, the LND317 has full overload
protection available only in integrated circuits.
Included on the chip are current limit, thermal
overload protection, and safe-area protection. All
overload protection circuitry remains fully
functional even if the adjustment terminal is
disconnected. Normally, no capacitors are
needed unless the device is situated far from the
input filter capacitors in which case an input
bypass is needed. An optional output capacitor
can be added to improve transient response.
The primary applications of this device is that of a
programmable output regulator, but by connecting
a fixed resistor between adjustment terminal and
the output terminal, the device can be used as a
precision current regulator. Even though the
regulator is floating and sees only the input-to -
output differential voltage, use of these devices to
regulate output voltages that would cause the
maximum-rated differential voltage to be
exceeded if the output became shorted to ground
is not recommended.
3-Terminal Adjustable Regulators
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
TO-220
INPUT
OUTPUT
ADJUST
(Top View)
(unless otherwise noted)
LND317 Unit
Input-to-Output differential voltage, VI -VO40 V
Continuous total dissipation at 25ºC free-air
temperature 2W
Continuous total dissipation at (or below) at 25ºC case
temperature 15 W
Operating free-air, case, or virtual junction
temperature range 0 to 125 ºC
Storage temperature range -65 to 150 ºC
Lead temperature 1.6mm (1/16 inch) from case for 10
seconds 260 ºC
LND317
MIN MAX UNIT
Output current, IO10 1500 mA
Operating virtual junction temperature, TJ0 125 ºC
ABSOLUTE MAXIMUM RATING
LM317
RECOMMENDED OPERATING CONDITIONS
TYPICAL APPLICATION DATA
V
LND317
IN
Adjust
0.1
µ
F
V
IN
V
OUT
V
V
OUT
OUT
= V
(
)
1 +R2
R1
C1
+ I
Adj
R2
(see note A)
C2
(see note B)
F
µ
1
REF
R1
240
R2
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
Note A: Use of an Input Bypass Capacitor is recommended if regulator is far from filter capacitors
Note B: Use of an output capacitor improves transient response, but is optional.
LND317
Over recommended ranges of operating virtual junction temperature (unless otherwise noted) (see Note 1)
LM317
PARAMETER TEST CONDITIONS MIN TYP MAX
UNIT
TJ=MIN to
MAX 0.01 0.04
Input regulation( See Note 2) VI-VO= 3V to 40V,
(See Note 3) IO =10mA to
1.5A 0.02 0.07
% / V
VO=10 V, f=120 Hz 65
Ripple rejection VO=10 V, f=120 Hz
10-µF capacitor between ADJ and
ground
66 80 dB
VO ≤ 5V 525 mV
IO=10mA to 1.5 A,
TJ =25ºC,(See Note3) VO > 5V 0.1 0.5 %
VO ≤ 5V 20 70 mV
Output Regulation
IO =10mA to 1.5A,
(see note 3) VO > 5V 0.3 1.5 %
Output Voltage Change with
temperature TJ =MIN to MAX 1 %
Output voltage long-term
drift(see note 4)
After 1000h at TJ =MAX and
VI-VO=40V 0.3 1 %
Output noise voltage f = 10Hz to 10kHz, TJ= 25ºC 0.003 %
Minimum output current to
maintain regulation VI -VO = 40V 3.5 10 mA
VI -VO ≤ 15V 1.5 2.2
Peak output current VI -VO ≤ 40V, TJ =25ºC 0.15 0.4 A
Adjustment terminal current 50 100 µA
Change in adjustment-
terminal current
VI-VO =2.5V to 40V,
IO=10mA to 1.5A 0.2 5.0 µA
Reference voltage(output to
ADJ)
VI -VO = 3V to 40V, IO =10mA to 1.5A,
P≤15W 1.2 1.25 1.3 V
Unless otherwise noted, these specifications apply for the following test conditions: VI -VO=5V and IO= 0.5A. For conditions shown as
MIN or MAX, use the appropriate value specified under recommended operating conditions.
Notes:
1. All characteristics are measured with a 0.1-µF capacitor across the input and a 1-µF capacitor across the output.
2. Input regulation is expressed here as the percentage change in output voltage per 1-V change at the input.
3. Pulse testing techniques are used to maintain the junction temperature as close to the ambient temperature as possible.
Thermal effects must be taken into account separately.
4. Since long-term drift cannot be measured on the individual devices prior to shipment, this specification is not intended to be a
guarantee or warranty. It is an engineering estimate of the average drift to be expected from lot to lot.
ELECTRICAL CHARACTERISTICS
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
LND317
• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •
TYPICAL APPLICATIONS
V
LND317
IN OUT
Adjust
IN
V
V
50 mA Constant Current Battery Charger
24
V
IN
V
OUT
C1
IN
Adjust
LND317
OUT
V
V
C2
F
µ
10
D1 protects against C1
D2 protects against C2
Regulator with Protection Diodes
V
IN
V
IN
Adjust
LND317
OUT
V
Adj
I
OUT
I
OUT
)
R1
(
+ I
Adj
I
REF
V
=
1.25 V
R1
=
10 mA <=I
OUT
<= 1.5 A
Current Regulator
R2
R1
240
D2
D1
+
R1
