The SY88303BL low-power limiting post amplifiers are designed for use in fiber-optic receivers. These devices connect to typical transimpedance amplifiers (TIAs) . Th e linear signal output from TIAs can contain significant amounts of noise and may vary in amplitude over time. The SY88303BL quantizes these signals and output CML-level waveforms.

The SY88303BL operates from a single +3.3V power supply, over temperatures ranging from -40°C to +85°C. With their wide bandwidth and high gain, signals with data rates up to 3.2Gbps, and as small as 10mV PP , can be amplified to drive devices with CML/PECL inputs.

The device generates a loss-of-signal (LOS) open-collector TTL output. The LOS function is optimized to detect a wide input range, as shown in the typical operating characteristic curve on Page 6. A programmable loss-of-signal level-set pin (LOS LVL) sets the sensitivity of the input amplitude detection.

LOS asserts high if the input amplitude falls below the threshold sets by LOS LVL and de-asserts low otherwise. The enable bar input (/EN) de-asserts the true output signal without removing the input signal. The LOS output can be fed back to the /EN input to maintain output stability under a loss-of-signal condition. Typically, 3.5dB LOS hysteresis is provided to prevent chattering.

Additional Features

• Loss-of-signal detection circuit optimized to detect a wide input range
• Chatter-free Open-Collector TTL Loss-of-Signal (LOS) output
• Single 3.3V power supply
• 155Mbps to 3.2Gbps operation
• Low-noise CML data outputs
• Programmable LOS level set (LOS LVL)
• Available in a tiny 10-pin EPAD-MSOP and 16-pin MLF ® package