3.3V, 2.7Gbps SDH/SONET LASER DRIVER WITH AUTOMATIC POWER CONTROL

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1 3.3V, 2.7Gbps SH/SONET LASER RIVER WITH AUTOMATIC POWER CONTROL FEATURES ESCRIPTION Single 3.3V power supply Up to 2.7Gbps operation Rise/Fall times: < 75ps Independent programmable laser modulation and bias currents Bias current to ma and modulation current to 9mA Automatic average laser power control Bias and modulation current monitors Operating temperature range of 4 C to +85 C Complies with ANSI, ITU, and Bellcore SH/SONET specifications Available in IE form and 32-pin (5mm 5mm) EPA-MLF package APPLICATIONS OC-48 transceivers and transponders SONET/SH transmission system Add drop mux Metro area network 2.5Gbps optical transmitter Fiber optical module is a highly integrated and programmable laser driver for SONET/SH application up to 2.7Gbps. The device accepts differential PECL or LVS data and clock inputs. It provides programmable bias and modulation currents for driving a laser. The modulation output of can be C-coupled to drive the laser diode, providing a significant power saving over ACcoupled operation. A synchronizing TTL input latch can be used to reduce jitter if a clock signal is available. A TTL enable is also incorporated in the device. EN only enables/disables I MO. It does not enable/disable I BIAS. An automatic power controller (APC) is integrated into to maintain a constant average optical output power over temperature and lifetime. The modulation current can be externally temperature compensated to minimize the variation of extinction ratio of the optical output. Several safety features will enable an alarm function when the output signal is too high, or bias current is too high. There are two alarm conditions:. /FAIL asserts when bias current loop goes to maximum of it's range. I BIAS and I MO still flow under this condition. 2. /FAIL asserts when I BIASMAX or I MOSET are too high (implying I BIAS or I MO will be too high). All currents will shut off under this condition. MLF and MicroLeadFrame are trademarks of Amkor Technology, Inc. Rev.: B Amendment: / Issue ate: August 25

2 PACKAGE/ORERING INFORMATION / CLK /CLK LATCH BIASMAX MOSET SLOW M / / Ordering Information () Package Operating Package Lead Part Number Type Range Marking Finish MI MLF-32 Industrial Sn-Pb MITR (2) MLF-32 Industrial Sn-Pb MG MLF-32 Industrial with Pb-Free Pb-Free bar-line indicator NiPdAu MGTR (2) MLF-32 Industrial with Pb-Free Pb-Free bar-line indicator NiPdAu Notes: EN BIASMON MOMON /FAIL BIAS. ice are designed to operate from 4 C to +85 C, but are tested and guaranteed to T A = +25 C only. 2. Tape and Reel. 32-Pin MLF (MLF-32) PIN ESCRIPTION Pin Number Pin Name Pin Function 6 BIAS Bias Current Output (I BIAS ). BIASMON Bias Current Monitor: Sinks current that is proportional to I BIAS, (I BIAS /4). An external current path must exist to. 3 BIASMAX A resistor (R BIASMAX ) connected to ground sets the maximum bias current. See Typical Operating Characteristics (I BIAS vs. R BIASMAX ). 26 SLOW Connect a capacitor (C SLOW ) to ground to provide a slow-start. 5, 6 CLK,/CLK ifferential Clock Input. 75KΩ pull-down on CLK, 75kΩ pull-up and 75kΩ pull-down on /CLK. 2, 3, / ifferential ata Input. 75KΩ pull-down on, 75kΩ pull-up and 75kΩ pull-down on /. 9 EN TTL Input with 75kΩ pull-up: efault HIGH for normal operation; LOW to disable modulation current. 8 LATCH TTL Input with 75kΩ pull-up: efault HIGH for latched (clocked) data; LOW for direct data. 25 M Connect this pin to a monitor photodiode anode, a resistor (R APCSET ) and a capacitor (C APCSET ). This sets the desired average optical power. 9, 2, 22, 23, / ifferential Output: Modulation current output (I MO ). 2 MOMON Modulation Current Monitor: Sinks current that is proportional to I MO, (I MO /45). An external current path must exist to. 3 MOSET A resistor (R MOSET ) connected to ground sets the modulation current. See Typical Operating Characteristics (I MO vs. R MOSET ). 3 /FAIL TTL Open-Collector Output: Connect a 5kΩ resistor to. Indicates APC failure when LOW., 4, 7, 8, 2, 24, 32 Positive Power Supply., 4, 5, 7, evice Ground: Ensure the exposed pad is also connected to ground. 27, 28, 29, EP TRUTH TABLE () / EN OUT (2) /OUT L H H H L H L H L H X X L H L Note. L = LOW, H = HIGH, X = don't care. Note 2. H = I OUT I MO_OFF. 2

3 Absolute Maximum Ratings () Supply Voltage ( )... +V to +7.V Input Voltage (V IN )... +V to Output Current (I OUT )... ma Lead Temperature (soldering, sec.)... 3 C Storage Temperature (T S ) C to +5 C Operating Ratings (2, 3) Supply Voltage ( ) V to +3.6V Ambient Temperature (T A )... 4 C to +85 C Junction Temperature (T J )... 2 C Package Thermal Resistance MLF (θ JA ) still-air C/W (ψ JB ) still-air... 9 C/W C ELECTRICAL CHARACTERISTICS = 3.V to 3.6V; V EE = GN; R LOA = 5Ω; T A = 4 C to +85 C Symbol Parameter Condition Min Typ Max Units I CC Supply Current Note 4 85 ma I BIAS Bias Current Range Note 5 ma I MO Modulation Current Range Note 5 9 ma I MO_OFF Modulation Off Current Note 6 75 µa V I ifferential Input Voltage 2 6 mv PP V ICMR Common Mode Range.49 V I /4 V V IH TTL Input HIGH Voltage 2. V V IL TTL Input LOW Voltage.8 V V OL /FAIL Output LOW Voltage Note 6.5 V I OH /FAIL Output Leakage Current Note 7 µa Notes:. 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. 2. The data sheet limits are not guaranteed if the device is operated beyond the operating ratings. 3. evices are ES sensitive. Handling precautions recommended. 4. Excluding actual I BIAS and I MO output currents. 5. Voltage at, / must not drop below.5v. Voltage BIAS, MOMON and BIASMON must not drop below 2V. 6. EN = LOW. 7. I OL = +2mA. 8. V OH = 3.6V. 3

4 AC ELECTRICAL CHARACTERISTICS (9) = 3.V to 3.6V; V EE = GN; T A = 4 C to +85 C; typical = 3.3V, T A = 25 C, I MO = 4mA, I BIAS = 5mA, R LOA = 5Ω Symbol Parameter Condition Min Typ Max Units CI Maximum Consecutive 8 bits Identical igits PW Pulse Width istortion Note, 5 ps t S Latch Set-Up Time 4 ps t H Latch Hold Time 4 ps t r, t f Output Rise/Fall Time 75 ps (2% to 8%) Notes: 9. AC characteristics are guaranteed by design and characterization.. Measured with 622Mbps - pattern, latch = HIGH.. PW = (Wider pulse narrower pulse) /2. TIMING IAGRAM t CLK = 4ps CLK t S t H Setup/Hold Time efinition 4

5 TYPICAL OPERATING CHARACTERISTICS (NOTE ) = 3.3V, T A = 25 C, unless otherwise stated. I MO (ma) I MO vs. R MOSET R MOSET (Ω) I BIAS (ma) I BIAS vs. R BIASMAX R BIASMAX (Ω) GAIN (I MO /I MOMON ) Modulation-Current Monitor Gain 6 vs. Temperature I MO = 4mA, 5 I BIAS = 5mA I MO = ma, I BIAS = ma TEMPERATURE ( C) GAIN (I BIAS /I BIASMON ) Bias-Current Monitor Gain vs. Temperature I MO = ma, I BIAS = ma I MO = 4mA, I BIAS = 5mA I APCSET (ma) I APCSET vs. R APCSET TEMPERATURE ( C) R APCSET (KΩ) Note. I BIAS and I MO must never exceed ma and 9mA, respectively. 5

6 BLOCK IAGRAM LATCH / CLK MUX R EN Ω BIASMON I BIAS 4 X4 X4 BIAS Ω M MOMON I MO 45 Failure etect R APCSET C APCSET V REF C SLOW SLOW R MOSET MOSET R BIAS MAX BIASMAX /FAIL 5kΩ 6

7 32 LEA EPA-Micro LEAFRAME (MLF-32) Package EP- Exposed Pad ie CompSide Island Heat issipation Heat issipation Heavy Copper Plane V EE Heavy Copper Plane V EE PCB Thermal Consideration for 32-Pin MLF Package (Always solder to equivalent or PCB) MICREL, INC. 28 FORTUNE RIVE SAN JOSE, CA 953 USA TEL + (48) FAX + (48) 474- WEB The information furnished by Micrel in this datasheet 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 intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser s use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. 25 Micrel, Incorporated. 7