Product Brief Integrated Circuit Systems, Inc. M844 MULTI-RATE CLOCK RECOVERY DATA_IN PIN ASSIGNMENT (1.575 x 3.2 inch SMA) The M844 Multi-Rate Clock Recovery module provides low jitter clock recovery from NRZ or RZ input data formats. Four data rates are digitally selectable: 9.953, 10.3125, 10.664, or 10.709Gb/s. Incoming data is first amplified by a limiting amplifier. The data is then both: a) provided as the module’s unretimed data output, and b) applied to the clock recovery circuitry. A Phase Locked Loop (PLL) incorporates frequency multipliers and a SAW-based Voltage Control SAW Oscillator (VCSO) to minimize clock jitter. The VCSO provides the high Q, low noise, and high stability needed for the narrow bandwidth PLL operation. Micro-strip bandpass filters are used to produce sinusodal clock output with low harmonic and sub-harmonic distortion. M844 Din ALM GND GND VEE -5V 1/4 CLK_OUT • 4 selectable NRZ or RZ rates: 9.953, 10.3125, • • • • • • • • Cout Dout DATA_OUT VCC +5V 1/4Cout FEATURES 10.664, or 10.709Gb/s Superior VCSO-based PLL jitter performance 0.12 ps peak-to-peak max 0.02ps rms jitter, typical (12kHz-20MHz) Low phase noise -85dBc/Hz @ 1kHz offset 6mV peak-to-peak input sensitivity Up to 700mV peak-to-peak un-retimed NRZ or RZ data output +5V and -5V power supplies Designed for high-speed fiber optic applications Easy to connect 1.575 x 3.2 inch SMA package CONT 2 CONT 1 CLK_OUT GENERAL DESCRIPTION Example Input/Output Frequency Combinations Operating Data Rate (Gb/s) 9.9530 10.3125 10.6640 10.7090 Clock Output Freq (GHz) OC-192 OC-48 9.9530 2.488 10.3125 2.577 10.6640 2.666 10.7090 2.677 Application OC-192 BLOCK DIAGRAM M844 DATA_IN DATA_OUT Lim Amp RF Amp RF Amp 4x Frequency Multiplier RF Amp 2x Frequency Multiplier Pwr Div Phase Detector Pwr Div 2x Frequency Multiplier OpAmp CLK_OUT SAW Delay Lines 1 - 4 SP4T SW SP4T SW RF Amp Pwr Div 1/4CLK_OUT RF Amp Phase Shifter Rate Select M844 Rev 1.3 Revision 12Nov2003 M844 Multi-Rate Clock Recovery Integrated Circuit Systems, Inc. ● Communications Modules ● w w w. i c s t . c o m ● tel (508) 852-5400