NTE NTE914 Datasheet

NTE914

Integrated Circuit

Zero–Voltage Switch

Description:

The NTE914 zero–voltage switch is a monolithic silicon integrated circuit in a 14–Lead DIP type pack­age designed to control a thyristor in a variety of AC power switching applications for AC input voltages
of 24V, 120V, 208/230V, and 277V at 50/60Hz and 400Hz. The NTE914 incorporates 4 functional
blocks as follows:

Limiter–Power Supply: Permits operation directly from an AC line.
Differential ON/OFF Sensing Amplifier: Tests the condition of external sensors or command

signals. H ysteresis or p roportional–control c apability m ay e asily be implemented i n t his s ection.
Zero–Crossing Detector: Synchronizes the output pulses of the circuit at the time when the

AC cycle is at zero voltage point; thereby eliminating radio–frequency interference (RFI) when
used with resistive loads.

TRIAC Gating Circuit: Provides high current pulses to the gate of the power controlling thyristor.

The NTE914 also provides the following important auxiliary functions:

A built–in protection circuit that may be actuated to remove drive from the TRIAC if the sensor
opens or shorts.

Thyristor firing may be inhibited through the acting of an internal diode gate connected to Pin1.
High–power DC comparator operation is provided by overriding the action of the zero–crossing

detector. This is accomplished by connecting Pin12 to Pin7. Gate current to the thyristor is
continuous when Pin13 is positive with respect to Pin9.

Features:

D 24V, 120V, 208/230V, 277V at 50Hz, 60Hz, or 400Hz Operation
D Differential Input
D Low Balance Input Current: 1µA Max
D Built–In Protection Circuit or Opened or Shorted Sensor
D Sensor Range: R
D DC Mode
D External Trigger
D External Inhibit
D DC Supply Voltage: 14V Max

= 2 to 100kΩ

X

Applications:

D Relay Control
D Valve Control
D Synchronous Switching of Flashing Lights
D ON/OFF Motor Switching
D Differential Comparator with Self–Contained Power Supply for Industrial Applications
D Photosensitive Control
D Power One–Shot Control
D heater Control
D Lamp Control

Absolute Maximum Ratings:

(TA = +25°C unless otherwise specified)

DC Supply Voltage (Between Pin2 and Pin7) 14V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DC Supply Voltage (Between Pin2 and Pin8) 10V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Peak Supply Current (Between Pin5 and Pin7) ±50mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Output Pulse Current (Pin4) 150mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Power Dissipation (T

≤ +55°C), P

A

D

700mW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Derate Linearly Above 55°C 6.67mW/°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Ambient Temperature Range, T
Storage Temperature Range, T

stg

opr

Lead Temperature (During Soldering 1/16” from case, 10sec max), T

Electrical Characteristics:

(TA = +25°C, All voltages are measured with respect to Pin7 unless

L

–55° to +125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

–65° to + 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

+265°C. . . . . . . . . . . . . . . . .

otherwise specified)

Parameter Symbol Test Conditions Min Typ Max Unit

For Operation at 120V

DC Supply Voltage (Inhibit Mode)

At 50/60Hz

At 400Hz RS = 10kΩ, IL = 0 – 6.8 – V

DC Supply Voltage (Pulse Mode)

At 50/60Hz

At 400Hz RS = 10kΩ, IL = 0 – 6.7 – V
Gate Trigger Current IGT(4) VGT = 1V, Pin3 and Pin4 Connected – 105 – mA
Peak Output Current (Pulsed)

With Internal Power Supply

With External Power Supply V+ = 12V, VGT = 0, Pin3 Open – 170 – mA

Inhibit Input Ratio V9/V2Voltage Ratio of Pin9 to Pin2 0.465 0.485 0.520
Total Gate Pulse Duration

(Positive dv/dt)
50–60Hz

400Hz C
Total Gate Pulse Duration

(Negative dv/dt)
50–60Hz

400Hz C

, 50–60Hz (AC Line Voltage) (Note 1)

rms

V

V

IOM(4) VGT = 0, Pin3 Open 50 84 – mA

RS = 8kΩ, IL = 0 6.1 6.5 7.0 V

S

RS = 5kΩ, IL = 2mA – 6.4 – V

RS = 8kΩ, IL = 0 6.0 6.4 7.0 V

S

RS = 5kΩ, IL = 2mA – 6.3 – V

V

= 0, Pin3 and Pin2 Connected 90 124 – mA

GT

V+ = 12V, VGT = 0, Pin3 and Pin2 Connected – 240 – mA

t

P

C

= 0 70 100 140 µs

EXT

= 0, R

EXT

t

N

C

= 0 70 100 140 µs

EXT

= 0, R

EXT

EXT

EXT

= ∞ – 12 – µs

= ∞ – 10 – µs

Note 1. The values given in the “Electrical Characteristics” chart at 120V also apply for operation at

input voltages of 24V, 208/230V, and 277V, except for Pulse Duration. However, the series
resistor (R

) must have the indicated value shown in Table 1 for the specified value.

S