NTE NTE876 Datasheet

NTE876

Linear Integrated Circuit

LED Flasher/Oscillator

Description:

The NTE876 is monolithic oscillator specifically designed to flash Light Emitting Diodes. By using the
timing capacitor for voltage boost, it delivers pulses of 2 or more volts to the LED while operating on
a supply of 1.5V or less. The circuit is inherently self–starting, and requires the addition of only a bat­tery and capacitor to function as an LED flasher.

Packaged in an plastic 8–Lead mini–DIP, the NTE876 will operate over the extended consumer tem­perature range of –25°C to +70°C. It has been optimized for low power drain and operation from weak
batteries so that continuous operation life exceeds that expected from battery rating.

Timing capacitors will generally be of the electrolyic type, and a small 3V rated part will be suitable
for any LED flasher using a supply up to 6V . However, when picking flash rates, it should be remem­bered that some electrolyics have very broad capacitance tolerances, for example –20% to +100%.

Features:

D Operation over one year from one C size flashlight cell
D Bright, high current LED pulse
D Minimum external parts
D Internal Timing Resistor
D Internal LED Current Limiting Resistor
D Low voltage operation, from just over 1V to 5V
D Low current drain, averages under 0.5mA during battery life
D Powerful as an oscillator directly drives an 8Ω speaker

Applications:

D Finding flashlights in the dark, or locating boat mooring floats
D Sales and advertising gimmicks
D Emergency locators, for instance on fire extinguishers
D Toys and novelties: e.g., Siren for toy fire engine
D Electronic applications such as trigger and sawtooth generators
D Warning indicators powered by 1.4V to 200V

Absolute Maximum Ratings:

Supply Voltage, V+ 6.4V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Power Dissipation, P
Operating Temperature Range, T

D

opr

Lead Temperature (Soldering 10 sec), T

–25° to +70°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

L

500mW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

+260°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Characteristics:

Parameter Test Conditions Min Typ Max Unit

Supply Voltage In Oscillation 1.15 – 6.0 V
Operating Current – 0.55 0.75 mA
Flash Frequency 300µF, 5% Capacitor 0.65 1.0 1.3 Hz
High Flash Frequency 0.30µF, 5% Capacitor – 1.1 – kHz
Compatible LED Forward Drop IF = 1mA 1.35 – 2.1 V
Peak LED Current 350µF Capacitor – 45 – mA
Pulse Width 350µF Capacitors at 1/2 Amplitude – 6.0 – ms

Pin Connection Diagram

3K Fast RC

N.C.

V (–)

85

14

1

2
3

4

.300 (7.62) .300

8

9K Slow RC

7

N.C.Output
R

6

L

V (+)

5

.256 (6.52) Max

.150

(3.81)

(7.62)

.393 (10.0)

Max

.070 (1.77) Min.100 (2.54)