NTE NTE1901 Datasheet

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, P

Input–Output Voltage Differential, V
Operating Junction Temperature Range, T
Storage Temperature Range, T
Lead Temperature (During Soldering, 10sec), T

D

– V

I

O

J

stg

L

Internally Limited. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

40V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

–40° to +125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

–55° to +150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

+300°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Characteristics:

Parameter Symbol Test Conditions Min Typ Max Unit

Line Regulation Reg

Load Regulation Reg

Thermal Regulation TA = +25°C, 10ms Pulse – 0.04 0.2 %/W
Adjustment Pin Current I
Adjustment Pin Current Change I
Reference Voltage V

Temperature Stability T
Minimum Load Currnt I

MaximumOutput Current Limit I

RMS Output Noise, % of V
Ripple Rejection Ratio RR V

Long Term Stability S TJ = +125°C, 100 Hours – 0.3 1.0 %

(Note 1 unless otherwise specified)

= +25°C, 3V ≤ (VIN – VO) ≤ 40V, Note 2 – 0.01 0.04 %/V

3V ≤ (VIN – VO) ≤ 40V, Note 2 – 0.02 0.07 %/V

= +25°C, 5mA ≤ IO ≤ 100mA, Note 2 – 0.1 0.5 %

5mA ≤ IO ≤ 100mA, Note 2 – 0.1 0.5 %

5mA ≤ IL ≤ 100mA, 3V ≤ (VIN – VO) ≤ 40V – 0.2 5.0 µA
5mA ≤ IL ≤ 100mA, 3V ≤ (VIN – VO) ≤ 40V,

P ≤ 625mW, Note 3
–25°C ≤ TJ ≤ +125°C – 0.65 – %
(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

= –10V, f = 120Hz, C

OUT

C

= 10µF 66 80 – dB

ADJ

OUT

LineTA

LoadTA

Adj
Adj

ref

S

L(min)

max

N TA = +25°C, 10Hz ≤ f ≤ +10kHz – 0.003 – %

– 50 100 µA

1.20 1.25 1.30 V

= 0 – 65 – dB

ADJ

Note 1. Unless otherwise noted, these specifications apply: –25° ≤ TJ ≤ +125°C, VIN – V

= 40mA, and I

I

OUT

= 100mA. Although power dissipation is internally limited, these

MAX

OUT

= 5V,

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.