FEATURES ■ ■ ■ ■ ■ ■ SY88702 5V 622Mbps LASER DIODE DRIVER WITH OUTPUT ENABLE Micrel SY88702 DESCRIPTION Up to 622Mbps operation Modulation current to 25mA PECL output enable Differential PECL inputs Single 5V power supply Available in a tiny 10-pin (3mm) MSOP The SY88702 is a high-speed current switch for driving a semiconductor laser diode in optical transmission applications. The modulation current (IOUT) is controlled by the current (IRSET) through the external resistor RSET. The output OUT is HIGH and no current flows through OUT when output enable is HIGH. The device incorporates complementary open collector outputs with 25mA maximum current driving capability. The external resistor R EXT must be placed between /OUT and VCC to dissipate the worst case power. RSER is recommended to compensate for laser diode matching issues. The SY88702 utilizes the high performance bipolar ASSET™ technology. APPLICATIONS ■ 622Mbps SONET FUNCTIONAL BLOCK DIAGRAM VCC REXT /OUT OUT RSER DIN /DIN to Laser Diode Internal Logic IMOD /EN 40X VCC GND VEE VREF RSET RSET ASSET is a trademark of Micrel, Inc. Rev.: B 1 Amendment: /0 Issue Date: August 2003 SY88702 Micrel PACKAGE/ORDERING INFORMATION Ordering Information /EN 1 10 VCC Part Number Package Type Operating Range Package Marking DIN 2 9 OUT SY88702KC K10-1 Commercial 702 /DIN 3 8 /OUT SY88702KCTR* K10-1 Commercial 702 VREF 4 7 GND SY88702KI K10-1 Industrial 702 RSET 5 6 GND SY88702KITR* K10-1 Industrial 702 *Tape and Reel 10-Pin MSOP (K10-1) PIN DESCRIPTION Pin Number Pin Name Pin Function 1 /EN 2, 3 DIN, /DIN 4 VREF Voltage reference for use with RSET. 5 RSET An external resistor connected from here to VREF sets the reference current for IOUT. 6, 7 GND Device ground. 9, 8 OUT, /OUT 10 VCC 100k PECL compatible input with 75kΩ pull-down resistor. Modulation current goes to zero when deasserted high. Differential 100k PECL compatible input with 75kΩ pull-down resistors. Differential open collector current outputs. Positive power supply. TRUTH TABLE(1) D /D /EN OUT (2) /OUT L H L H L H L L L H X X H H L Note 1. L = LOW, H = HIGH, X = don't care. Note 2. H = IOUT = 0mA. 2 SY88702 Micrel Absolute Maximum Ratings(Note 1) Operating Ratings(Notes 2,3,4) Power Supply Voltage (VCC) ............................ 0V to +7.0V Input Voltage (VIN) .............................................. 0V to VCC Output Current (IOUT) ................................................. 25mA Power Dissipation (PD) ........................................... 250mW Storage Temperature Range (TS) ............ –55°C to +125°C Supply Voltage (VCC) .................................. +4.5V to +5.5V Ambient Temperature (TA), Note 5 ............ –40°C to +85°C Junction Temperature (TJ), Note 5 ............ –40°C to 100°C Resistor to Dissipate Power (REXT) .................. 10Ω to 50Ω Laser Diode Serial Resistor (RSER) .................... 0Ω to 50Ω Resistor to Adjust Current (RSET) .......... 1500Ω to 50,000Ω Package Thermal Resistance MSOP (θJA) Still-Air ...................................................... 113°C/W (ψJB) Still-Air ........................................................ 74°C/W DC ELECTRICAL CHARACTERISTICS GND = 0V; VCC = 5V ±10%; TA = –40°C to +85°C Symbol Parameter Condition Min VIH Input HIGH Voltage (DIN, /DIN, /EN) VIL Input LOW Voltage (DIN, /DIN, /EN) VREF Reference Voltage IIL Input LOW Current (DIN, /DIN, /EN) IIH Input HIGH Current (DIN, /DIN, /EN) ICC Supply Current IOUT_OFF Output LOW Current (/EN = HIGH) IOUT Modulation Current 5 ARSET IOUT/IRSET 30 VOUT Voltage at OUT, /OUT COUT Capacitance on OUT, /OUT Typ Max Units VCC–1.165 VCC–0.880 V VCC–1.810 VCC–1.475 V 3.00 VIN = VIL(min) V µA 0.5 IMOD = 25mA 100 µA 25 mA 500 µA 15 25 mA 38 44 — VCC V 16 VCC–2.3 2.5 pF 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. Note 2. The data sheet limits are not guaranteed if the device is operated beyond the operating ratings. Note 3. The device is guaranteed to meet the DC specifications, shown in the table above, after thermal equilibrium has been established. The device is tested in a socket such that transverse airflow of ≥500lfpm is maintained. Note 4. The voltage drop across REXT and RSER plus Laser Diode must not be greater than 2.3V. Note 5. Commercial devices are guaranteed from 0°C to +85°C ambient temperature. 3 SY88702 Micrel AC ELECTRICAL CHARACTERISTICS(Note 1) GND = 0V; VCC = 5V ±10%; TA = –40°C to +85°C Symbol Parameter Condition tPHL, tPLH D Propagation Delay DIN – OUT tPHL, tPLH EN Propagation Delay /EN – OUT tr tf Rise/Fall Time (20% to 80%) IOR Output Current Ringing Note 1. Min Max Units IOUT = 10mA 1000 ps IOUT = 10mA 1000 ps 400 ps 10 % IOUT = 5 to 25mA REXT = RSER = 50Ω ±1%; RSER connected directly to VCC. TYPICAL OPERATING CHARACTERISTICS IMOD vs. RSET 30 25 IMOD (mA) 20 15 10 5 0.0 0.0 2.0K 4.0K 6.0K W RSET ( ) 4 8.0K 10K 12K Typ SY88702 Micrel 10 LEAD MSOP (K10-1) Rev. 00 MICREL, INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB USA http://www.micrel.com 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. © 2003 Micrel, Incorporated. 5