5V/3.3V 2.5Gbps Micrel, Inc. SY88943V LIMITING POST AMPLIFIER SY88943V WITH SIGNAL DETECT DESCRIPTION FEATURES 3.3V and 5V power supply options The SY88943V limiting post amplifier with its high gain and wide bandwidth is ideal for use as a post amplifier in Up to 2.5Gbps operation fiber-optic receivers with data rates up to 2.5Gbps. Low noise Signals as small as 5mVp-p can be amplified to drive Chatter-fee signal detect (SD) generation devices with PECL inputs. The SY88943V generates a Open collector TTL signal detect (SD) output chatter-free Signal Detect (SD) open collector TTL output. The SY88943V incorporates a programmable level detect TTL EN input function to identify when the input signal has been lost. Differential PECL inputs for data The SD output will change from logic HIGH to logic LOW Single power supply when input signal is smaller than the swing set by SD . LVL Designed for use with Micrel-Synergy laser diode This information can be fed back to the EN input of the driver and controller device to maintain stability under loss of signal condition. Using SD pin, the sensitivity of the level detection can Available in a tiny (3mm) 10-pin MSOP LVL be adjusted. The SD voltage can be set by connecting LVL a resistor divider between V and V as shown in Figure CC REF 3. Figure 4, 5, 6, and 7 show the relationship between APPLICATIONS input level sensitivity and the voltage set on SD . LVL The SD output is a TTL open collector output that 1.25Gbps and 2.5Gbps ethernet requires a pull-up resistor for proper operation, Figure 1. 531Mbps, 1062Mbps and 2.12Gbps Fibre Channel 622Mbps SONET V CC Gigabit interface converter SY88943V 2.5Gbps SDH/SONET 4.7k to 10k SD 2.5Gbps proprietary links Figure 1. SD Output with Desired Rise Time BLOCK DIAGRAM D IN D OUT Limiting ECL Amplifer Buffer /D IN /D OUT Enable EN V REF V CC Level Detect GND SD SD LVL Rev.: C Amendment: /0 M9999-082205 11 Issue Date: August 2005 hbwhelp micrel.com or (408) 955-1690Micrel, Inc. SY88943V PACKAGE/ORDERING INFORMATION Ordering Information EN 1 10 VCC Package Operating Package Lead DIN 2 9 DOUT Part Number Type Range Marking Finish MSOP /DIN 3 8 /DOUT SY88943VKC K10-1 Commercial 943V Sn-Pb K10-1 (1) VREF 4 7 SD SY88943VKCTR K10-1 Commercial 943V Sn-Pb SDLVL 5 6 GND SY88943VKG K10-1 Commercial 943V with Pb-Free Pb-Free bar-line indicator NiPdAu (1) SY88943VKGTR K10-1 Commercial 943V with Pb-Free 10-Pin MSOP (K10-1) Pb-Free bar-line indicator NiPdAu Note: 1. Tape and Reel. PIN NAMES GENERAL DESCRIPTION General Pin Type Function The SY88943V is an integrated limiting amplifier intended D Data Input Data Input IN for high-frequency fiber-optic applications. The circuit /D Data Input Inverting Data Input IN connects to typical transimpedance amplifiers found within SD Input SD Level Set a fiber-optics link. The linear signal output from a LVL transimpedance amplifier can contain significant amounts EN TTL Input Output Enable (Active High) of noise, and may vary in amplitude over time. The SD TTL Output Signal Detect SY88943V limiting amplifier quantizes the signal and outputs (Open Collector) a voltage-limited waveform. GND Ground Ground The EN pin allows the user to disable the output signal without removing the input signal. /D PECL Output Inverting Data Output OUT D PECL Output Data Output OUT V Power Supply Positive Power Supply CC V Output Reference Voltage Output for REF SD Level Set (see Fig. 3) (1) ABSOLUTE MAXIMUM RATINGS Symbol Rating Value Unit V Power Supply Voltage 0 to +7.0 V CC D , /D Input Voltage 0 to V V IN IN CC D , /D Output Voltage (with 50 load) V 2.5 to V +0.3 V OUT OUT CC CC EN Input Voltage 0 to V V CC SD Input Voltage 0 to V V LVL CC V Output Voltage V 2.0 to V V REF CC CC T Operating Temperature Range 40 to +85 C A T Storage Temperature Range 55 to +125 C store Note: 1. Permanent device damage may occur if absolute maximum ratings are exceeded. This is a stress rating only and functional operation is not implied at conditions other than those detailed in the operational sections of this data sheet. Exposure to absolute maximum ratlng conditions for extended periods may affect device reliability. M9999-082205 2 hbwhelp micrel.com or (408) 955-1690