7239

NTE7239
Integrated Circuit
Positive Adjustable Voltage Regulator,
5A, 1.2V to 32V
TO−220 Type Package
Description:
The NTE7239 is an adjustable 3−terminal positive voltage regulator in a TO−200 type package capable of supplying in excess of 5A over a 1.2V to 32V output range. A unique feature of this device is
time−dependent current limiting, which allows peak current up to 12A to be drawn from the regulator
for short periods of time. his allows the NTE7239 to be used with heavy transient loads and speeds
start−up under full−load conditions. Under sustained loading conditions, the current limit decreases
to a safe value protecting the regulator. Also included on th chip are thermal overload protection, and
safe area protection for the power transistor. Overload protection remains functional even if the adjustment pin is accidentally disconnected.
Normally, no capacitors are needed unless the device is situated more than 6 inches from the input
filter capacitors in which case an input bypass is needed. An output capacitor can be added to improve
transient response, while bypassing the adjustment pin will increase th regulator’s ripple rejection.
Besides replacing fixed regulators o discrete designs, the NTE7239 is useful in a wide variety of other
applications. Since the regulator is “floating” and sees only the input−to−output differential voltage,
supplies of several hundred volts can be regulated as long as the maximum input to output differential
is not exceeded, i.e., do not short−circuit output to ground.
Features:
D Specified 7A Peak Output Current
D Specified 5A Output Current
D Adjustable Output Down to 1.2V
D Specified Thermal Regulation
D Current Limit Constant with Temperature
D Output is Short−Circuit Protected
Applications:
D Adjustable Power Supplies
D Constant Current Regulators
D Battery Chargers
Absolute Maximum Ratings: (Note 1)
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally Limited
Input/Output Voltage Differential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +40V, −0.3V
Note 1. Absolute maximum ratings indicate limits beyond which damage to the device may occur.
Operating ratings indicate conditions for which the device is intended to be functional, but
do not ensure specific performance limits. For ensured specifications and test conditions,
see the Electrical Characteristics.
Absolute Maximum Ratings (Cont’d): (Note 1)
Operating Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to +125C
Storage Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65 to +150C
Lead Temperature (During Soldering, 4 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +260C
Typical Thermal Resistance, Junction−to−Ambient (No Heat Sink), RthJA . . . . . . . . . . . . . . 50C/W
Maximum Thermal Resistance, Junction−to−Case, RthJC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4C/W
Note 1. Absolute maximum ratings indicate limits beyond which damage to the device may occur.
Operating ratings indicate conditions for which the device is intended to be functional, but
do not ensure specific performance limits. For ensured specifications and test conditions,
see the Electrical Characteristics.
Electrical Characteristics: (TJ = +25C, VIN = VOUT = 5V, IOUT = 10mA, Note 2 unless otherwise
specified)
Parameter
Reference Voltage
Line Regulation
Load Regulation
Symbol
Test Conditions
Min
Typ
Max
Unit
VREF
3V  (VIN − VOUT)  35V, 10mA  IOUT  5A,
P  50W, 0  TJ  +125C
1.19
1.24
1.29
V
−
0.005
0.03
%/V
−
0.02
0.06
%/V
−
0.1
0.5
%
−
0.3
1.0
%
20ms Pulse
−
0.002
0.02
%/W
VRLINE
VRLOAD
3V  (VIN − VOUT)  35V,
Note 3
0  TJ  +125C
10mA  IOUT  5A
0  TJ  +125C
Thermal Regulation
Adjustment Pin Current
IADJ
0  TJ  +125C
−
45
100
A
Adjustment Pin Current
Change
IADJ
3V  (VIN − VOUT)  35V, 10mA  IOUT  5A,
0  TJ  +125C
−
0.2
5.0
A
Temperature Stability
VR/T
0  TJ  +125C
−
1
−
%
−
3.5
10
mA
5
8
−
A
7
12
−
A
Minimum Load Current
Current Limit
DC
ILOAD(Min) VIN − VOUT = 35V, 0  TJ  +125C
ICL
VIN − VOUT  10V, 0  TJ  +125C
0.5ms Peak
Current Limit
ICL
VIN − VOUT = 30V
−
−
1
A
RMS Output Noise,
%of VOUT
VN
10Hz  f  10kHz
−
0.003
−
%
CADJ = 0F
−
60
−
dB
CADJ = 10F
60
75
−
dB
−
0.3
1.0
%
Ripple Rejection Ratio
Long−Term Stability
VR/VIN
VOUT = 10V, f = 120Hz,
0  TJ  +125C
TJ = +125C, 1000 hrs
Note 2. These specifications are applicable for power dissipation up to 25W. Power dissipation is
specified up to 15V input−output differential. Above 15V differential, power dissipation will
be limited by internal protection circuitry.
Note 3. Regulation is measured at a constant junction temperature, using pulse testing with a low
duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation.
.420 (10.67)
Max
.110 (2.79)
.147 (3.75)
Dia Max
.500
(12.7)
Max
.250 (6.35)
Max
.500
(12.7)
Min
.070 (1.78) Max
Adjust
.100 (2.54)
VIN
VOUT/Tab