Chipanalog CA-IF4023

CA-IF4023 is a fully integrated transceiver compliant with the AISG 3.0 standard. The CA-IF4023 receiver features a 20dB input dynamic range and integrates a narrowband active bandpass filter centered at 2.176MHz, ensuring the receiver can demodulate useful signals even in the presence of interfering signals. The CA-IF4023 transmitter also integrates a narrowband active bandpass filter centered at 2.176MHz to ensure the output spectrum meets the AISG 3.0 standard. The output power is adjustable from 5.4dBm to 12dBm via an external resistor to compensate for power loss on the coaxial cable. The CA-IF4023 supports direction control for RS-485 bus arbitration and accepts input from an external crystal, oscillator, or other external clock source. The CA-IF4023 receive chain includes a narrowband bandpass filter centered at 2.176MHz, an OOK demodulator, and an output driver, enabling correct demodulation of useful signals in the presence of interference. The typical demodulation threshold of the receive chain is –15±2dBm, compliant with the AISG standard specification. The CA-IF4023 transmit chain includes an OOK modulator, a bandpass filter conforming to the AISG spectrum mask, and an output amplifier. The transmit chain output power is adjustable via an external resistor network to compensate for power loss caused by external circuitry and coaxial cables, with an adjustable range of +5.4dBm to +12dBm (corresponding to –0.6dBm to +6dBm at the cable output). An 8.704MHz external crystal input via the XTAL1 and XTAL2 ports generates the OOK modulated carrier signal. Alternatively, an external clock signal of the same frequency can be input via the XTAL1 port as the carrier signal, in which case the XTAL2 port must be grounded. The CA-IF4023 provides a direction indicator output port (DIR) to indicate the direction of signal flow, facilitating faster and more convenient bus arbitration for RS-485. Ports DIRMD1 and DIRMD2 are used to set the BIT time for different signal rates. When both DIRMD1 and DIRMD2 are pulled high to VL, the device enters standby mode, in which RXOUT is forced high, no input signal on RXIN is demodulated, DIR is forced low, and the overall supply current of the device decreases.

• Analog supply voltage range: 3V to 5.5V
• Logic supply voltage range: 1.6V to 5.5V
• Receiver wide input dynamic range: –15dBm to +5dBm
• Transmitter output power adjustable: 5.4dBm to 12dBm
• Transmit characteristics compliant with AISG 3.0
• Low-power standby mode
• Direction control for RS-485 bus arbitration
• Supports all AISG signaling rates: 9.6kbps, 38.4kbps, 115.2kbps
• On-chip active bandpass filter with 2.176MHz center frequency
• 3mm×3mm 16-lead QFN package
• Operating temperature range: –40°C to 125°C

• AISG interface for antenna line devices
• Tower Mounted Amplifier (TMA)
• Universal modem interface