S107_15 Datasheet, PDF (3/5 Pages) Solid State Optronic – High transient immunity

S107
1 Form A
Solid State Relay
PERFORMANCE DATA
S107
Maximum Load Current vs. Temperature
1000
800
600
400
200
0
-40 -20
0 _{20 40 60 80}
Tem perature (C)
S107
Typical Blocking Voltage Distribution
N = 100, Ambient Temperature = 25°C
50
40
30
20
10
0
620 630 640 650 660 670 680 690
Blocking Voltage (V)
ZERO-VOLT SWITCHING
This solid state relay has been designed with a driver circuit that controls the operation of two back-to-back silicon controlled rectifiers
(SCRs), each responsible for one half of the AC cycle. If an AC signal is examined, the turn on, turn off and zero-volt switching can be seen.
Figure 1 shows a typical 60 Hz, 120Vac signal with a corresponding relay input signal:
1
Relay Input Signal is
Turned On.
5 _{Relay Input Signal is}
Turned Off.
Input Signal
5V
Threshold
2 ^{SCR #1 Turns On when}
5V threshold is reached.
6 _{SCR #1 and Relay Turn}
Off at Zero Volts.
3
SCR #1 Turns Off,
SCR #2 Turns On
at Zero Volts.
4
SCR #2 Turns Off,
SCR #1 Turns On
at Zero Volts.
Figure 1 shows the sequence of zero-volt switching operation. At Stage 1, an input signal is applied to the relay. The relay will not turn on
until the threshold voltage of 5V is reached. Once this point is reached (Stage 2), SCR #1 (designated as the SCR which controls positive
AC voltage) turns on. However, SCR #1 only conducts for an instant, as the cycle quickly crosses zero. At this point (Stage 3), SCR #1 will
turn off and SCR #2 (negative AC voltage) turns on. Likewise, at the next zero cross (Stage 4), SCR #2 will turn off and SCR #1 conducts
again. Even though the input signal is terminated at Stage 5, the relay will continue to conduct (typical SCR behavior) until Stage 6, when
SCR #1 crosses zero and ceases to conduct. Please note that turn on can likewise begin on the negative phase of the AC cycle with a -5V
threshold, though only the positive phase is shown here.
© 2007 Solid State Optronics • San José, CA
www.ssousa.com • +1.408.293.4600
Page 3 of 5
S107
rev 1.41 (10/23/2007)