28-Gbps low-power 4-channel limiting transimpedance amplifier with RSSI

The ONET2804TLP device is a high-gain, limiting transimpedance amplifier (TIA) for parallel optical interconnects with data rates up to 28 Gbps. The device is used in conjunction with a 750-µm pitch photodiode array to convert an optical signal into a differential output voltage. An internal circuit provides the photodiode reverse bias voltage and senses the average photocurrent supplied to each photodiode.

The device can be used with pin control or a two-wire serial interface to allow control of the output amplitude, gain, bandwidth, and input threshold.

The ONET2804TLP provides 17.5-GHz bandwidth, a gain of 7.5 kΩ, an input-referred noise of 2 µArms, and a received signal strength indicator (RSSI) for each channel. 40-dB isolation between channels results in low crosstalk penalty in the receiver.

The device requires a single 2.8-V to 3.3-V supply and typically dissipates 90 mW per channel with a differential output amplitude of 300 mVPP. The device is characterized for operation from –40°C to +100°C and is available in die form with a 750-µm channel pitch.