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. Hysteresis or proportional–control capability may easily be implemented in this section. 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: RX = 2 to 100kΩ D DC Mode D External Trigger D External Inhibit D DC Supply Voltage: 14V Max 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 (TA ≤ +55°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700mW Derate Linearly Above 55°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.67mW/°C Operating Ambient Temperature Range, Topr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –55° to +125°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to + 150°C Lead Temperature (During Soldering 1/16” from case, 10sec max), TL . . . . . . . . . . . . . . . . . +265°C Electrical Characteristics: (TA = +25°C, All voltages are measured with respect to Pin7 unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit 6.1 6.5 7.0 V RS = 5kΩ, IL = 2mA – 6.4 – V RS = 10kΩ, IL = 0 – 6.8 – V RS = 8kΩ, IL = 0 6.0 6.4 7.0 V RS = 5kΩ, IL = 2mA – 6.3 – V RS = 10kΩ, IL = 0 – 6.7 – V For Operation at 120Vrms, 50–60Hz (AC Line Voltage) (Note 1) DC Supply Voltage (Inhibit Mode) At 50/60Hz VS At 400Hz DC Supply Voltage (Pulse Mode) At 50/60Hz VS At 400Hz RS = 8kΩ, IL = 0 Gate Trigger Current IGT(4) VGT = 1V, Pin3 and Pin4 Connected – 105 – mA Peak Output Current (Pulsed) With Internal Power Supply IOM(4) VGT = 0, Pin3 Open 50 84 – mA VGT = 0, Pin3 and Pin2 Connected 90 124 – mA V+ = 12V, VGT = 0, Pin3 Open – 170 – mA V+ = 12V, VGT = 0, Pin3 and Pin2 Connected – 240 – mA With External Power Supply Inhibit Input Ratio Total Gate Pulse Duration (Positive dv/dt) 50–60Hz V9/V2 tP 400Hz Total Gate Pulse Duration (Negative dv/dt) 50–60Hz 400Hz tN Voltage Ratio of Pin9 to Pin2 0.465 0.485 0.520 CEXT = 0 70 100 140 µs CEXT = 0, REXT = ∞ – 12 – µs CEXT = 0 70 100 140 µs CEXT = 0, REXT = ∞ – 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 (RS) must have the indicated value shown in Table 1 for the specified value. Electrical Characteristics (Cont’d): (TA = +25°C, All voltages are measured with respect to Pin7 unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit – 50 – µs For Operation at 120Vrms, 50–60Hz (AC Line Voltage) (Note 1) Pulse Duration After Zero Crossing (50–60Hz) For Positive dv/dt tP1 For Negative dv/dt tN1 – 60 – µs Output Leakage Current (Inhibit Mode) I4 – 0.001 10 µs Input Bias Current II – 220 1000 nA CEXT = 0, REXT = ∞ Common–Mode Input Voltage Range VCMR Pin9 and Pin13 Connected Sensitivity (Pulse Mode) ∆V13 Pin12 Open, Note 2 1.5 to 5.0 – 6 V – mV 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 (RS) must have the indicated value shown in Table 1 for the specified value. Note 2. Required voltge change at Pin13 to either turn OFF the TRIAC or turn ON the TRIAC when OFF. Table 1: AC Input Voltage (50/60 or 400Hz) Input Series Resistor, RS Dissipation Rating for RS V AC kW W 24 2 0.5 120 10 2.0 208/230 20 4.0 277 25 5.0 Pin Connection Diagram Inhibit Input 1 14 Failsafe Input Sensor Network 2 13 Sensor Network Current Boost 3 12 Zero–Crossing Det Input Thyristor Gate 4 11 Off–On Sense Amp AC Input 5 10 Off–On Sense Amp External Trigger 6 9 Off–On Sense Amp Common 7 8 Common 14 8 1 7 .785 (19.95) Max .300 (7.62) .200 (5.08) Max .100 (2.45) .600 (15.24) .099 (2.5) Min