SI87XX Datasheet, PDF (12/36 Pages) Silicon Laboratories – 5 KV LED EMULATOR INPUT, OPEN COLLECTOR OUTPUT ISOLATORS

Si87xx
2. Application Information
2.1. Theory of Operation
The Si87xx are pin-compatible, one-channel, drop-in replacements for popular optocouplers with data rates up to
15 Mbps. The operation of an Si87xx channel is analogous to that of an opto coupler, except an RF carrier is
modulated instead of light. This simple architecture provides a robust isolated data path and requires no special
considerations or initialization at start-up. A simplified block diagram for the Si87xx is shown in Figure 5.
Transmitter
RF
OSCILLATOR
Receiver
Semiconductor-
A
LED
Emulator
MODULATOR
Based Isolation
Barrier
DEMODULATOR
Output Stage
Open Collector
B
Figure 5. Simplified Channel Diagram
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Preliminary Rev. 0.5