sy88343hl 3.3v, 3.2gbps cml limiting post amplifier with high - gain ttl loss - of - signal micrel inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel +1 (408) 944 - 0800 ? fax + 1 (408) 474 - 1000 ? http://www.micrel.com august 2007 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 general description the sy88343hl low - power, high - sensitivity, limiting, post amplifier is designed for use in fiber - optic receivers. the device connects to typical transimpedance amplifiers (tias). the linear signal output from tias can contain signific ant amounts of noise and may vary in amplitude over time. the sy88343hl quantizes these signals and outputs cml level waveforms. the sy88343hl operates from a single +3.3v power supply, over temperatures ranging from ? 40 o c to +85 o c. with its wide bandwidth , high gain, and signals with data rates up to 3.2gbps and as small as 4mv pp , it can be amplified to drive devices with cml/pecl inputs the sy88343hl generates a high - gain loss - of - signal (los) open - collector ttl output. this function has a high - gain input stage for increased los sensitivity. 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 set by los lvl and de - asserts low otherwise. t he 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 pre vent chattering. all support documentation can be found on micrel?s web site at: www.micrel.com . features ? high input sensitivity: 4mv pp ? single 3.3v power supply ? 155mbps to 3.2gbps operation ? ideal for multi - rate app lications ? low - noise cml data outputs ? high - sensitivity loss - of - signal (los) detection ? chatter - free open - collector ttl loss - of - signal (los) output with internal 4.75k ? pull - up resistor ? ttl /en input ? programmable los level set (los lvl ) ? available in a tiny (3m m x 3mm) 16 - pin qfn package applications ? apon, bpon, epon, gepon, and gpon ? sfp/sff/gbic optical transceivers ? gigabit ethernet ? 1x and 2x fibre channel ? sonet/sdh: oc 3/12/24/48 ? stm ?/8/16 ? line driver and line receiver markets ? fttx ? datacom/telecom typical application sy88343hl
micrel, inc. sy88343hl august 2007 2 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 ordering information part number package type operating range package marking lead finish SY88343HLMG qfn -16 industrial 343h with pb - free bar line indicator nipdau pb - free SY88343HLMGtr (1) qfn -16 industrial 343h with pb - free bar line in dicator nipdau pb - free note: 1. tape and reel. pin configuration 16- pin qfn pin description pin number pin name type pin function 15 /en ttl input: default is high. /enable: this input enables the outputs when it is low. note that this input is intern ally connected to a 25k ? pull - up resistor and will default to logic high state if left open. 1 din data input true data input. 4 /din data input complementary data input. 6 vref reference voltage: bypass with 0.1 f low esr capacitor from vref to v cc to stabilize los lvl and v ref . 14 loslvl input loss -of - signal level set: a resistor from this pin to v cc sets the threshold for the data input amplitude at which los will be asserted. 2, 3, 10, 11 gnd, exposed pad ground device ground. gnd and exposed pad are to be tied to the sa me ground plane. 7 los open - collector ttl output w/internal 4.75k ? pull - down resistor loss -of - signal: asserts high when the data input amplitude falls below the threshold sets by los lvl . 9 /dout cml output complementary data output. 12 dout cml output true data output. 5, 8, 13, 16 vcc power supply positive power sup ply.
micrel, inc. sy88343hl august 2007 3 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 absolute maximum ratings (1) supply voltage (v cc ) .................................... 0v to +4.0v input voltage (din, /din) ................................... 0 to v cc output current (i out )???? .... ???????25ma /en voltage ........................................................ 0 to v cc v ref current??????????? - 800 a to + 500 a los lvl voltage .............................................. v ref to v cc lead temperature (solde ring, 20sec.) .................. 260c storage temperature (t s ) ..................... - 65c to +150c operating ratings (2) supply voltage (v cc ) .............................. +3.0v to +3.6v ambient temperature (t a ) .................... ? 40c to +85c junction temperature (t j ) .................. ? 40c to +125c junction thermal resistance qfn ( ja ) still - air ..................................................... 61c /w qfn ( jb ) junction - to - board ..................................... 38 o c/w dc electrical characteristics v cc = 3.0v to 3.6v; r l = 50 ? to v cc ; t a = ? 40c to +85c. symbol parameter condition min typ max units i cc power supply current no output load 45 62 ma los lvl los lvl voltage v ref v cc v v oh cml output high voltage v cc - 0.020 v cc - 0.005 v cc v v ol cml output low voltage v cc = 3.3v v cc - 0.475 v cc - 0.400 v cc - 0.350 v v offset differential output offset 80 mv z o single - ended output impedance 40 50 60 ? v ref reference voltage v cc - 1.28 v v ihcmr input common mode range gnd+2.0 v cc v ttl dc electrical characteristics v cc = 3.0v to 3.6v; r l = 50 ? to v cc ; t a = ? 40c to +85c. symbol parameter condition min typ max units v ih /en input high voltage 2.0 v il /en input low vo ltage 0.8 v i ih /en input high current v in = 2.7v v in = v cc 20 100 a a i il /en input low current v in = 0.5v -300 a v oh los output high level v cc > 3.3v, i oh - max < 160a v cc < 3.3v, i oh - max < 160a 2.4 2.0 v v v ol los output low level i ol = +2ma 0.5 v notes: 1. permanent device damage may occur if absolute maximum ratings are exceeded. this is a stress rating only and functional opera tion is not implied at conditions other than those detailed in the operational sections of this data sheet. exposure to absolute maximum rating conditions for extended periods may affect device reliability. 2. the data sheet limits are not guaranteed if the device is operated beyond the operating ratings. 3. package thermal resistance assumes exposed pad is sol dered (or equivalent) to the device?s most negative potential (gnd) on the pcb. jb uses 4 - layer ( ja ) in still - air - number, unless otherwise stated.
micrel, inc. sy88343hl august 2007 4 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 ac electrical characteristics v cc = 3.0v to 3.6v; r l = 50 ? to v cc ; t a = ? 40c to +85c. symbol parameter condition min typ max units t r , t f output rise/fall time (20% to 80%) note 4 6 0 120 ps t jitter deterministic random note 5 note 6 15 5 ps pp ps rms v id differential input voltage swing figure 1 3 1800 mv pp v od differential output voltage swing v id > 4mv pp , figure 1 700 800 950 mv pp t off los release time 2 10 s t on los asser t time 2 10 s los al low los assert level r loslvl = 15k ?, note 8 3.0 mv pp los dl low los de - assert level r loslvl = 15k ?, note 8 4.5 mv pp hys l low los hysteresis r loslvl = 15k ?, note 7 3.5 db los am medium los assert level r loslvl = 5k ?, note 8 2 5.0 mv pp los dm medium los de - assert level r loslvl = 5k ?, note 8 7.5 11 mv pp hys m medium los hysteresis r loslvl = 5k ?, note 7 2 3.5 4.5 db los ah high los assert level r loslvl = 100 ?, note 8 8 12 mv pp los dh high los de - assert level r loslvl = 100 ?, not e 8 18 23 mv pp hys h high los hysteresis r loslvl = 100 ?, note 7 2 3.5 4.5 db b - 3db 3db bandwidth 2 ghz a v(diff) differential voltage gain 40 46 db s 21 single - ended small - signal gain 34 40 db notes: 4. amplifier in limiting mode. input is a 200m hz square wave. 5. deterministic jitter measured using 3.2gbps k28.5 pattern, v id = 10mv pp . 6. random jitter measured using 3.2gbps k28.7 pattern, v id = 10mv pp . 7. this specification defines electrical hysteresis as 20log (los de - assert/los assert). the ra tio between optical hysteresis and electrical hysteresis is found to vary between 1.5 and 2, depending upon the level of received optical power and rosa characteristics. b ased on that ratio, the optical hysteresis corresponding to the electrical hysteresis range 2db - 4.5db, shown in the ac characteristics table, will be 1db - 3db optical hysteresis. 8. see ?typical operating characteristics? for a graph showing how to choose a particular r loslvl for a particular los assert and its associated de- assert amplitud e.
micrel, inc. sy88343hl august 2007 5 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 typical operating characteristics functional characteristics
micrel, inc. sy88343hl august 2007 6 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 functional block diagram detailed description the sy88343hl high - sensitivity limiting post amplifier operates from a single +3.3v power supply, over temperatur es from ? 40 o c to +85 o c. signals with data rates up to 3.2gbps and as small as 4mv pp can be amplified. figure 1 shows the allowed input voltage swing. the sy88343hl generates a los output. los lvl sets the sensitivity of the input amplitude detection. input amplifier/buffer figure 2 shows a simplified schematic of the sy88343hl?s input stage. the high - sensitivity of the input amplifier allows signals as small as 4mv pp to be detected and amplified. the input amplifier also allows input signals as large as 1800 mv pp . input signals below 6mvpp are linearly amplified with a typical 46db differential voltage gain. since it is a limiting amplifier, the sy88343hl outputs typically 800mv pp voltage - limited waveforms for input signals than 6mv pp . applications requiring t he sy88343hl to operate with high - gain should have the upstream tia placed as close as possible to the sy88343hl?s input pins to ensure the best performance of the device. output buffer the sy88343hl ?s cml output buffer is designed to drive 50 ? lines. the output buffer requires appropriate termination for proper operation. an external 50 ? resistor to v cc for each output pin provides this. figure 3 shows a simplified schematic of the output stage. l oss - of - signal the sy88343hl generates a chatter - free los open - collector ttl output with an internal 4.75k ? pull - up resistor as shown in figure 4. los is used to determine that the input amplitude is large enough to be considered a valid input. los asserts high if the input amplitude falls below the threshold set by los lvl and de - asserts low otherwise. los can be fed back to the enable bar (/en) input to maintain output stability under a loss of signal condition. /en de - asserts the true output signal without removing the input signals. typically, 3.5db los hysteresis is provided to prevent chattering. loss - of - signal level set a programmable los level set pin (los lvl ) sets the threshold of the input amplitude detection. connecting an external resistor between v cc and los lvl sets the voltage at los lvl . this voltage ranges from v cc to v ref . the external resistor creates a voltage divider between v cc and v ref , as shown, in figure 5. hysteresis the sy88343hl typically provides 3.5db los electrical hysteresis. by de finition, a power ratio measured in db is 10log (power ratio). power is calculated as v 2 in /r for an electrical signal. hence, the same ratio can be stated as 20log (voltage ratio). while in linear mode, the electrical voltage input changes linearly with th e optical power and therefore, the ratios change linearly. thus, the optical hysteresis in db is half the electrical hysteresis in db given in the data sheet. since the sy88343hl is an electrical device, this data sheet refers to hysteresis in electrical t erms. with 3.5db los hysteresis, a voltage factor of 1.5 is required to assert or de - assert los.
micrel, inc. sy88343hl august 2007 7 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 figure 1. v is and v id definition figure 2. input structure figure 3. output structure figure 4. input structure figure 5. los lvl setting circ uit
micrel, inc. sy88343hl august 2007 8 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 package information pcb thermal consideration for 16 - pin qfn package package notes: 1. package meets level 2 qualification. 2. all parts are dry - packaged before shipment. 3. exposed pad must be soldered to a ground for proper thermal management.
micrel, inc. sy88343hl august 2007 9 m9999 - 082007-a hbwhelp@micrel.com or (408) 955 - 1690 micrel, inc. 2180 fortune drive san jose, ca 95131 usa tel +1 (408) 944 - 0800 fax +1 (408) 474 - 1000 web http://www.micrel.com the information furnished by micrel in t his data sheet is believed to be accurate and reliable. however, no responsibility is assumed by micrel for its use. micrel reserves the right to change circuitry and specifications at any time without notification to the customer. micrel products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. life support devices or systems are devices or systems that (a) are intende d for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to res ult in a significant injury to the user. a purchaser?s use or sale of micrel products for use in life support appliances, dev ices or systems is a purchaser?s own risk and purchaser agrees to fully indemnify micrel for any damages resulting from such use or sale. ? 2007 micrel, incorporated.
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