LM1893N Carrier-Current Transceiver RH IC DIP-18
The LM1893N is a bipolar carrier-current transceiver IC that uses building AC power mains as the communications medium for half-duplex serial data links. It implements a current-controlled oscillator whose output is shaped to a low-RFI sinusoid, and the chip provides the on-chip drive needed to couple an FSK carrier onto a power-line coupling transformer and through a coupling capacitor to the AC wiring.
In transmit mode the device FSK-modulates a 50–300 kHz carrier under control of baseband data; an internal automatic-level-control plus a robust output amplifier produce a controlled current into the tank/coupling network so the line sees a sinusoidal carrier with limited distortion. In receive mode the input from the coupling transformer passes a band-limited, Norton-style limiter and a PLL demodulator; an impulse-noise integrator and offset-cancel loop recover clean digital edges for the host controller.
The LM1893N is intended as the interface between digital controllers (microcontrollers/COPSTM) and the power line, enabling modest-rate serial links (hundreds to a few thousand baud) with strong impulse-noise immunity. The device is designed so external discrete components (transformer, coupling cap, loop-filter, impulse filter) let designers trade sensitivity, data rate, and noise rejection for their application.
Features:
- Noise resistant FSK modulation.
- User-selected impulse noise filtering.
- Up to 4.8 kBaud data transmission rate.
- Strings of 0’s or 1’s in data allowed.
- Sinusoidal line drive for low RFI.
- Output power easily boosted 10-fold.
- 50 to 300 kHz carrier frequency choice.
- TTL and MOS compatible digital levels.
- Regulated voltage to power logic.
- Drives all conventional power lines.
Specifications:
| Parameter (selected) | Value / Range |
|---|---|
| Supply voltage (absolute max): | 30 V |
| Carrier I/O peak survivable transient (pin 10): | 80 V min limit 60 V |
| Operating ambient temperature: | −40°C to +85°C |
| Max continuous dissipation (plastic DIP N, TA=25°C): | Transmit mode 1.66 W Receive mode 1.33 W |
| Carrier frequency (programmable): | 50 – 300 kHz |
| Max data rate (receiver functional): | Up to 4.8 kBaud (depends on FO and filters) |
| Typical supply/current (transmit example at Va=18V): | Total IQT ≈ 52 mA (see table for ranges) |
| Receiver sensitivity (to chip side, FO dependent): | ≈1.4–2.0 mVRMS (FO dependent); referred to line side lower (example 0.20–0.29 mVRMS) |
| Data Out breakdown voltage (pin 12): | Min 70 V |
| Package (order): | LM1893N – molded DIP (NS package N18A) |
Applications:
- Energy management systems.
- Home convenience control.
- Inter-office communication.
- Appliance control.
- Fire alarm systems.
- Security systems.
- Telemetry.
- Computer terminal interface.
Package Contents:
- 1x LM1893N Carrier-Current Transceiver RH IC DIP-18
