MAX3664

19-0479; Rev 1; 7/97 622Mbps, Ultra-Low-Power, 3.3V Transimpedance Preamplifier for SDH/SONET ________________General Description The MAX3664 low-power transimpedance preamplifier for 622Mbps SDH/SONET applications consumes only 85mW. Operating from a single +3.3V supply, it converts a small photodiode current to a measurable differential voltage. A DC cancellation circuit provides a true differential output swing over a wide range of input current levels, thus reducing pulse-width distortion. The differential outputs are back-terminated with 60Ω per side. The transimpedance gain is nominally 6kΩ. For input signal levels beyond approximately 100µAp-p, the amplifier will limit the output swing to 900mV. The MAX3664’s low 55nA input noise provides a typical sensitivity of -33.2dBm in 1300nm, 622Mbps receivers. The MAX3664 is designed to be used in conjunction with the MAX3675 clock recovery and data retiming IC with limiting amplifier. Together, they form a complete 3.3V, 622Mbps SDH/SONET receiver. In die form, the MAX3664 is designed to fit on a header with a PIN diode. It includes a filter connection, which provides positive bias for the photodiode through a 1kΩ resistor to VCC. The device is also available in 8-pin SO and µMAX packages. KIT ATION EVALU E L B AVAILA ____________________________Features o Single +3.3V Supply Operation o 55nARMS Input-Referred Noise o 6kΩ Gain o 85mW Power o 300µA Peak Input Current o 200ps Max Pulse-Width Distortion o Differential Output D...