HFM1222-331

HFM1222 Token Ring Receiver FEATURES • -31 dBm to -11 dBm sensitivity • Differential data outputs (ECL compatible) • Signal Quality Detect output (open collector) • Output squelch input (TTL) • Adjustable signal quality detect level • ST¨ interface • 500 í output drive capability • Monolithic design - less board space, high reliability • 4 and 16 Mbps operation FIBER101.TIF DESCRIPTION The HFM1222 Token Ring fiber optic receiver module is designed for use in computer LAN (16 Mb/s Token Ring) applications. The 9 pin module is intended to meet IEEE 802.5J signal standards. OUTLINE DIMENSIONS in inches (mm) A PIN photodiode plus pre-amp is mounted in the fiber optic connector for maximum shielding, and provides amplification and current-to-voltage conversion. The post-amp IC provides final amplification to the logic output levels (see Block Diagram). Differential Data, Signal Quality Detect output, and Output Squelch input are available. Differential ECL output allows capacitive coupling to ECL logic and other differential line receivers. The HFM1222 has a 500 ohm output drive capability. An internally regulated power supply increases power supply rejection. Case ground is separated from circuit ground, allowing feedthrough mounting of the barrel. APPLICATION Average-to-peak input level monitoring generates the signal quality detect signal (Ç) when the input level is adequate for 10øÀÉ BER. The open collector output timing response of Ç is intended to meet 802.5J requirements over -31 dBm to -11 dBm average power levels. Note that the differential outputs are true with the light "on". ODIM_204.cdr Pinout 1. GND ground 6. Squelch 2. VÙÙ 7. Not connected 3. Output + 8. ADJ 4. Output - 9. Ç 5. O GND 576 h Honeywell reserves the right to make changes in order to improve design and supply the best products possible. HFM1222 Token Ring Receiver APPLICATION (continued) SQUELCH input is a TTL logic level. When it is high, it will disable the data outputs to prevent noise on the ECL outputs. With SQUELCH high, the outputs go to the same state as Light On at the input. It can be connected directly to the Ç output to squelch the outputs under low light conditions (receiver noise would cause unwanted chatter). Resistor Rà°¤ adjusts the Ç threshold upward. A resistor applied from ADJ to ground can be used to adjust the receiver's Ç threshold upward by 0 to 3.2 dB (optically). The ratio increase in threshold is given by: (Rà°¤ + 24.3K)/(Rà°¤ + 11.6K). ST is a registered trademark of AT & T. Honeywell reserves the right to make changes in order to improve design and supply the best products possible. h 577 HFM1222 Token Ring Receiver ELECTRO-OPTICAL CHARACTERISTICS (Over 0 to 70¡C, VÙÙ = 4.75 to 5.25 VDC unless otherwise stated) PARAMETER SYMBOL Data Rate (operating range) Input Power (operating range) MIN TYP 4 -31 Supply Current Jitter (uncorrelated) [À] [Á] Pulse Width Distortion [À] [Á] Signal Quality Detect (Ç) Delay Time (acceptable level) [Â] Delay Time (unacceptable level) [Â] Output (Out+/Out-) Load Output Swing 21 -34 13 4.5 500 1.6 Ç VÞÚ Receiver Bandwidth Signal Quality Detect (Ç) [Ã] [Ä] Signal Quality Detect, Hysteresis Output Rise and Fall Time [Å] Squelch Input MAX UNITS TEST CONDITIONS 16 -11 MBPS dBm 35 0.55 6 -31 18 7 mA ns ns dBm µs µs í V ppm/¡C V MHz dBm dB ns Manchester coding Average power (10øÀÉ BER) 850 nm Excluding Ç RMS, -31 dBm average input Average; -11 dBm input Threshold for Ç, high to low PÛÜ > -31 dBm average PÛÜ < -11 dBm average Peak to peak (differential) 25¡C Over temperature IÞÚ – 3 mA Small signal Transition for Ç low to high For low to high transition -31 dBm input V V mA mV(pk-pk) VÛÝ VÛÚ IÛÚ At 16 MHz 2.3 +1000 0.4 44 -38 0.3 1.5 3.3 2 0.8 0.16 100 Power Supply Rejection [Æ] Notes 1. Measured with 50% level of output with a 16 MHz, 50% duty cycle square wave input. 2. Measured with an input optical rise/fall time less than 6 ns. 3. Measured with a 16 MHz square wave input switched between light on and light off with a 60 µsec period in each state. 4. The Ç line will be high for any input power at this or lower input powers. 5. The BER will be 0.01 or better. 6. Load at each output is 500 ½ in parallel with 5 pf to AC ground. 7. Maximum power supply noise at 16 MHz to keep BER < 10øÀÉ at 31 dBm. ABSOLUTE MAXIMUM RATINGS Supply voltage (VÙÙ) < 7.0 V RECOMMENDED OPERATING CONDITIONS Supply voltage (VÙÙ) 4.75 to 5.25 V Temperature Temperature -40 to +85¡C Stresses greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. 0 to +70¡C ORDER GUIDE Description Catalog Listing Fiber Optic Token Ring receiver, 9 pin Package HFM1222-331 CAUTION The inherent design of this component causes it to be sensitive to electrostatic discharge (ESD). To prevent ESD-induced damage and/or degradation to equipment, take normal ESD precautions when handling this product. 578 h Honeywell reserves the right to make changes in order to improve design and supply the best products possible. HFM1222 Token Ring Receiver FIBER INTERFACE Honeywell receivers are designed to interface with multimode fibers (50/125 to 200/230 micron diameter). Final testing is performed with a 62.5/125 micron core fiber. Low cost 50/125 and 62.5/125 micron fibers are good for high bandwidth applications. 100/140 and 200/230 micron fibers result in greater power coupling by the transmitter, making it easier to splice or connect in bulkhead areas. TYPICAL CIRCUIT CONFIGURATION FIBER014.CIR BLOCK DIAGRAM FIBER010.SCH Fig. 1 Spectral Responsivity FIBER129.GRA Honeywell reserves the right to make changes in order to improve design and supply the best products possible. h 579