644.53125 MHz
OP4012B Performance Parameters
Optical Timing Clock
The OP4012B has been developed to achieve high performance in five parameters critical to optical data communications
applications:
Low Jitter and Phase Noise
- low clock jitter (or low phase noise in the frequency domain) is critical to achieving low bit error
rates in optical data communications systems. The OP4012B provides very low free-running jitter and phase noise as shown
in Figures 1 and 2. This makes the OP4012B an excellent reference for the generation or regeneration of low-jitter clocks
and data streams. The OP4012B achieves this performance over its full -40 to +85 °C operating temperature range using
RFM's patented SAW oscillator architecture.
Single-Sideband Phase Noise
Figure 1
High Power Supply Noise Immunity
- the OP4012B uses both differential active devices and differential SAW technology to
minimize the effects of power supply noise on jitter and phase noise, as shown in Figures 2 and 3. Optical data communi-
cations circuits must switch relatively high levels of current, making power supply noise immunity an important clock require-
ment.
Controlled Tuning Characteristics
- the OP4012B voltage tuning constant, K
V
, is bounded between 100 and 260 ppm/V un-
der locked conditions for reference signals with ±100 ppm or better stability over the OP4012B's full operating temperature
and supply voltage range. This allows a PLL based on the OP4012B to be designed with a well-controlled loop bandwidth
and damping factor, avoiding problems such a jitter peaking, etc. The voltage tuning characteristic of the OP4012B is mono-
tonic from 0 to 3.3 V, supporting reliable acquisition of phase lock. Figure 4 shows typical OP4012B tuning characteristics.
RF Monolithics, Inc.
Phone: (972) 233-2903
Fax: (972) 387-8148
RFM Europe
Phone: 44 1963 251383
Fax: 44 1963 251510
©2001 by RF Monolithics, Inc. The stylized RFM logo are registered trademarks of RF Monolithics, Inc.
E-mail: info@rfm.com
http://www.rfm.com
OP4012B-041003
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RFM [ RF MONOLITHICS, INC ]
