GENERAL DESCRIPTION

The ML4622 and ML4624 data quantizers are low noise, wideband, bipolar monolithic ICs designed specifically for signal recovery applications in fiberoptic receiver systems. They contain a wideband limiting amplifier which is capable of accepting an input signal as low as 2mVP-P with a 55dB dynamic range. This high level of sensitivity is achieved by using a DC restoration feedback loop which nulls any offset voltage produced in the limiting amplifier.

The output stage is a high speed comparator circuit with both TTL and ECL outputs. An enable pin is included for added control.

The Link Detect circuit provides a Link Monitor function with a user selectable reference voltage. This circuit monitors the peaks of the input signal and provides a logic level output indicating when the input falls below an acceptable level. This output can be used to disable the quantizer and/or drive an LED, providing a visible link status.

FEATURES

■ Data rates up to 40MHz or 80MBd

■ Can be powered by either +5V providing TTL or raised ECL level outputs or –5.2V providing ECL levels

■ Low noise design: 25µV RMS over bandwidth

■ Adjustable Link Monitor function with hystersis

■ Wide 55dB input dynamic range

■ Low power design

■ ML4624 is pin compatible with the ML4621

APPLICATIONS

■ IEEE 802.3 10BASE-FL Receiver

■ IEEE 802.5 fiber optic token ring, 4 and 16mbps

■ Fiber Optic Data Communications and Telecommunications Receivers