966

NTE966
Integrated Circuit
3−Terminal Positive Voltage Regulator, 12V
The NTE966 fixed−voltage regulator is a monolithic integrated circuit in a TO220 type package designed for use in a wide variety of applications including local, on−card regulation. This regulator employs internal current limiting, thermal shutdown, and safe−area compensation. With adequate heatsinking it can deliver output currents in excess of 1.0 ampere.
Features:
D Output Current in Excess of 1.0 Ampere
D No External Components Reguired
D Internal Thermal Overload Protection
D Internal Short−Circuit Current Limiting
D Output Transistor Safe−Area Compensation
Absolute Maximum Ratings: (TA = +25°C unless otherwise specified)
Input Voltage, Vin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Vdc
Power Dissipation (TA = +25°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally Limited
Derate above +25°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.4mW/°C
Power Dissipation (TC = +25°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally Limited
Derate above +75°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200mW/°C
Thermal Resistance, Junction−to−Ambient, RthJA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C/W
Thermal Resistance, Junction−to−Case, RthJC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5°C/W
Operating Junction Temperature Range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −55° to +150°C
Storage Junction Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65° to +150°C
Electrical Characteristics: (Vin = 19V, IO = 500mA, TJ = 0° to +125°C unless otherwise specified)
Parameter
Output Voltage
Line Regulation
Load Regulation
Symbol
VO
Regline
Regload
Test Conditions
Min
Typ
Max
Unit
TJ = +25°C
11.5 12.0 12.5
V
5mA ≤ IO ≤ 1A, PO ≤ 15W, 14.5V ≤ Vin ≤ 27V
11.4 12.0 12.6
V
TJ = +25°C, Note 1
TJ = +25°C, Note 1
14.5V ≤ Vin ≤ 20V
−
13
240
mV
16V ≤ Vin ≤ 22V
−
6
120
mV
5mA ≤ IO ≤ 1.5A
−
45
160
mV
250mA ≤ IO ≤ 750mA
−
16
80
mV
Note 1. Load and line regulation are specified at constant junction temperature. Changes in VO due
to heating effects must be taken into account separately. Pulse testing with low duty cycle
is used.
Electrical Characteristics (Cont’d): (Vin = 19V, IO = 500mA, TJ = 0° to +125°C unless otherwise
specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Quiescent Current
IB
TJ = +25°C
−
4.4
8.0
mA
Quiescent Current Change
∆IB
14.5V ≤ Vin ≤ 30V
−
−
1.0
mA
5mA ≤ IO ≤ 1A
−
−
0.5
mA
15V ≤ Vin ≤ 25V, f = 120Hz
−
60
−
dB
TJ = +25°C, IO = 1A
−
2
−
V
Ripple Rejection
RR
Dropout Voltage
Vin − VO
Output Noise Voltage
Vn
TA = +25°C, 10Hz ≤ f ≤ 100kHz
−
10
−
µV/VO
Output Resistance
rO
f = 1kHz
−
18
−
mΩ
Short−Circuit Current Limit
Isc
TA = +25°C, Vin = 35V
−
0.2
−
A
TJ = +25°C
−
2.2
−
A
−
−1.0
−
mV/°C
Peak Output Current
Imax
Average Temperature Coefficient
of Output Voltage
TCVO
Application Information:
The NTE966 fixed−voltage regulator is designed with Thermal Overload Protection that shuts down
the circuit when subjected to an excessive power overload condition, Internal Short−Circuit Protection
that limits the maximum current the circuit will pass, and Output Transistor Safe−Area Compensation
that reduces the output short−circuit current as the voltage across the pass transistor is increased.
In many low current applications, compensation capacitors are not required. However, it is recommended that the regulator input be bypassed with a capacitor if the regulator is connected to the power
supply filter with long wire lengths, or if the output load capacitor is large. An input bypass capacitor
should be selected to provide good high−frequency characteristics to insure stable operation under
all load conditions. A 0.33µF or larger tantalum, mylar, or other capacitor having low internal impedance at high frequencies should be chosen. The bypass capacitor should be mounted with the shortest possible leads directly across the regulators input terminals. Normally good construction techniques should be used to minimize ground loops and lead resistance drops since the regulator has
no external sense leads.
Current Regulator
Adjustable Output Regulator
NTE966
Output
NTE966
Input
0.33µF
R
Constant
Current to
Grounded Load
7
2
0.33µF
IO
6
NTE941
0.1µF
3
10k
1k
4
The NTE966 regulator can also be used as a current source when connected as above. Resistor
R determines the current as follows:
5V
IO =
+ IQ
R
IQ ` 1.5mA over line and load changes
For example, a 1−ampere current source would require R to be a 5Ω, 10W resistor and the output
voltage compliance would be the input voltage less 7 volts.
VO, 7V to 20V
VIN VO ≥ 2V
The addition of an operational amplifier allows adjustment to higher or intermediate values while
retaining regulation characteristics. The minimum voltage obtainable with this arrangement is 2
volts greater than the regulator voltage.
Current Boost Regulator
Short−Circuit Protection
NTE219
Input
RSC
Input
NTE219
NTE218
R
NTE966
1.0µF
Output
R
NTE966
Output
0.1µF
1.0µF
The NTE966 can be current bolosted with a PNP transistor. The NTE219 provides current to 5
amperes. Resistor R in conjunction with the VBE of the PNP determines when the pass transistor
begins conducting; this circuit is not short−circuit proof. Input−output differential voltage minimum
is increased by VBE of the pass transistor.
The “Current Boost Regulator” circuit can be modified to provide supply protection against
shout circuits by adding a short−circuit sense resistor, RSC, and an additional PNP transistor.
The current sensing PNP must be able to handle the short−circuit current of the three−ternimal
regulator. Therefor, a four−ampere plastic power transistor is specified.
.420 (10.67)
Max
.110 (2.79)
GND
.147 (3.75)
Dia Max
.500
(12.7)
Max
.250 (6.35)
Max
.070 (1.78)
Max
VIN
.100 (2.54)
.500
(12.7)
Min
VOUT
GND