NTE NTE1901

NTE1901
Integrated Circuit
Negative Adjustable Voltage Regulator,
–1.2V to –37V, 100mA
Description:
The NTE1901 is an adjustable 3–terminal negative voltage regulator in a TO92 type package capable
of supplying 100mA over a –12,V to –37V output range. It is exceptionally easy to use and both line
and load regulation are better than standard fixed regulators.
In addition to higher performance than fixed regulators, the NTE1901 offers full overload protection.
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 more than 6 inches from the input
filter capacitor in which case an input bypass is needed. An optional output capacitor can be added
to improve transient response. The adjustment terminal can be bypassed to achieve very high ripple
rejection ratios which are difficult to achieve with standard 3–terminal regulators.
Besides replacing fixed regulators, the NTE1901 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.
Also, it makes an especially simple adjustable switching regulator, a programmable output regulator,
or by connecting a fixed resistor between the adjustment and output, the NTE1901 can be used as
a precision current regulator. Supplies with electronic shutdown can be achieved by clamping the
adjustment terminal to ground which programs the output to 1.2V where most loads draw little current.
Features:
D Adjustable Output Down to 1.2V
D Guaranteed 100mA Output Current
D Line Regulation Typically 0.01%/V
D Load Regulation Typically 0.1%
D Current Limit Constant with Temperature
D Eliminates the Need to Stock Many Voltages
D Standard 3–Lead Transistor Package
D 80db Ripple Rejection
D Output is Short Circuit Protected
Absolute Maximum Ratings: (TA = +25°C unless otherwise specified)
Power Dissipation, PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally Limited
Input–Output Voltage Differential, VI – VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40V
Operating Junction Temperature Range, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40° to +125°C
Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –55° to +150°C
Lead Temperature (During Soldering, 10sec), TL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +300°C
Electrical Characteristics: (Note 1 unless otherwise specified)
Parameter
Line Regulation
Load Regulation
Symbol
Test Conditions
Min
Typ
Max
Unit
RegLine
TA = +25°C, 3V ≤ (VIN – VO) ≤ 40V, Note 2
–
0.01
0.04
%/V
3V ≤ (VIN – VO) ≤ 40V, Note 2
–
0.02
0.07
%/V
RegLoad TA = +25°C, 5mA ≤ IO ≤ 100mA, Note 2
–
0.1
0.5
%
5mA ≤ IO ≤ 100mA, Note 2
–
0.1
0.5
%
TA = +25°C, 10ms Pulse
–
0.04
0.2
%/W
–
50
100
µA
Thermal Regulation
Adjustment Pin Current
IAdj
Adjustment Pin Current Change
IAdj
5mA ≤ IL ≤ 100mA, 3V ≤ (VIN – VO) ≤ 40V
–
0.2
5.0
µA
Reference Voltage
Vref
5mA ≤ IL ≤ 100mA, 3V ≤ (VIN – VO) ≤ 40V,
P ≤ 625mW, Note 3
1.20
1.25
1.30
V
Temperature Stability
TS
–25°C ≤ TJ ≤ +125°C
–
0.65
–
%
Minimum Load Currnt
IL(min)
(VIN – VO) ≤ 40V
–
3.5
5.0
mA
3V ≤ (VIN – VO) ≤ 15V
–
2.2
3.5
mA
3V ≤ (VIN – VO) ≤ 13V
100
200
300
mA
(VIN – VO) ≤ 40V
25
50
150
mA
TA = +25°C, 10Hz ≤ f ≤ +10kHz
–
0.003
–
%
VOUT = –10V, f = 120Hz, CADJ = 0
–
65
–
dB
CADJ = 10µF
66
80
–
dB
TJ = +125°C, 100 Hours
–
0.3
1.0
%
MaximumOutput Current Limit
RMS Output Noise, % of VOUT
Ripple Rejection Ratio
Long Term Stability
Imax
N
RR
S
Note 1. Unless otherwise noted, these specifications apply: –25° ≤ TJ ≤ +125°C, VIN – VOUT = 5V,
IOUT = 40mA, and IMAX = 100mA. Although power dissipation is internally limited, these
specifications are applicable for power dissipations up to 625mW.
Note 2. Regulation is measured at constant junction temperature, using pulse testing with low duty
cycle. Changes in output voltage due to heating effects are covered under the specifications
for thermal regulation.
Note 3. Thermal resistance o the TO92 package is 180°C/W junction to ambient with 0.4” leads from
a PC board and 160°C/W junction to ambient with 0.125” lead length to PC board.
.135 (3.45) Min
.210
(5.33)
Max
Seating
Plane
.500
(12.7)
Min
.021 (.445) Dia Max
Adjust
VIN
VOUT
.100 (2.54)
.050 (1.27)
.105 (2.67) Max
.205 (5.2) Max
.165 (4.2) Max
.105 (2.67) Max