September 1998 ML6633* High Speed Fiber Optic LED Driver GENERAL DESCRIPTION FEATURES The ML6633 is a high speed fiber optic LED driver suited for networking applications up to 200 Mbps. The part is capable of driving up to 82mA of current through a fiber optic LED from an ECL level input signal. Its efficient output stage provides a high current that can be programmed for accurate absolute output level which insures precise launch power. n Data rates up to 200Mbps The LED driver’s output stage provides a fast well matched rise and fall time through a unique differential output stage. n Low EMI/RFI Noise The ML6633 high speed fiber optic LED driver is implemented in BiCMOS process and is available in an 8-pin SOIC package. n Industrial temperature version available n Current driven output for accurate launch power n Programmable output current from 20mA to 82mA n High Efficiency Output Stage n ECL inputs n May be used with ML6622 quantizer APPLICATIONS n FDDI n Fast Ethernet, 100BASE-FX n ATM (SONET), 155Mbps n Proprietary high-speed fiber optic data links BLOCK DIAGRAM *Some Packages Are Obsolete IOUT ECLP 2 ECLN 3 8 + + BUFFER DRIVER – – 7 RTSET 6 VCC REF GND 5 1 ML6633 PIN CONNECTION ML6633 8-Pin SOIC (S08) NC 1 8 VCC ECLP 2 7 IOUT ECLN 3 6 RTSET NC 4 5 GND TOP VIEW PIN DESCRIPTION PIN NAME DESCRIPTION 1 NC No Connect 2 ECLP Positive ECL data input controls signal to the LED 3 ECLN Negative ECL data input 4 NC No Connect 5 GND Negative power supply ground 2 PIN NAME DESCRIPTION 6 RTSET Output current programming pin. Connect a resistor of value 2/ILED from this pin to ground to set the high LED output current 7 IOUT Fiber optic LED drive pin. Connect the LED between this pin and VCC 8 VCC 5V power supply ML6633 ABSOLUTE MAXIMUM RATINGS Storage Temperature .............................. –65°C to +150ºC Lead Temperature (Soldering 10 sec) ....................... 260ºC Thermal Resistance (θJA) ................................... 160ºC/W Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. OPERATING CONDITIONS VCC ..................................................... GND –0.3V to 6V Input Pin Voltages .................... GND –0.3V to VCC +0.3V LED Output Current (IOUT) .................................... 82mA Peak DC Output Current (IOUT) ............................. 82mA Temperature Range ML6633CS .................................................... 0ºC to 70ºC ML6633IS.................................................. –40ºC to 85ºC ELECTRICAL CHARACTERISTICS Unless otherwise specified, VCC = 5V ± 5%, RTSET = 26.1Ω ± 1%, TA = Operating Temperature Range, (Note 1) SYMBOL ICC PARAMETER CONDITIONS MIN TYP Supply Current ILEDH ILEDL LED Current Accuracy (IOUT) High Low MAX UNITS 40+IOUT mA C Suffix 70 75 82 mA I Suffix 65 75 82 mA 0.1 mA tR Rise Time (IOUT) 2 ns tF Fall Time (IOUT) 2 ns Low to High 10 ns High to Low 10 ns tPLH Propagation Delay (IOUT) tPHL tPWD Pulse Width Distortion (IOUT) 0.5 ns IECL ECL Input Current 20 µA Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst-case test conditions. 3 ML6633 FUNCTIONAL DESCRIPTION The ML6633 accepts ECL input signals and generates a high speed, high accuracy output current which is independent of supply voltage variations. The output current is programmable up to 82mA. The ECL input stage is a standard NPN differential pair with a common mode range of between 1V and 4.5V with a +5V supply. With this common mode range it is possible to convert the ECL inputs into TTL. If the ECLN input is biased up to the TTL switching level, the ECLP pin can be driven by a TTL or CMOS output. Figure 1b shows a circuit implementing this technique. This circuit may degrade pulse width distortion and should be checked for acceptable performance in this configuration. NC Output current to the LED is set by connecting the appropriate resistance from RTSET to ground. The high level output voltage at RTSET will be 2.0V. The current in the external resistor will be equal to the current through the LED. The output current with RTSET set to 26.1Wwill be: ILED (HIGH) = 2V RTSET ILED (HIGH) = 2V = 75mA 26.1Ω 5V 5V 5V 5V VCC VIN+ ECLP IOUT VIN– ECLN RTSET GND NC a) IOUT = 75mA 5V NC TTLIN NC VCC ECLP IOUT ECLN RTSET GND b) ECL-to-TTL Conversion Figure 1. Typical Applications 4 (1) ML6633 PHYSICAL DIMENSIONS inches (millimeters) Package: S08 8-Pin SOIC 0.189 - 0.199 (4.80 - 5.06) 8 PIN 1 ID 0.148 - 0.158 0.228 - 0.244 (3.76 - 4.01) (5.79 - 6.20) 1 0.017 - 0.027 (0.43 - 0.69) (4 PLACES) 0.050 BSC (1.27 BSC) 0.059 - 0.069 (1.49 - 1.75) 0º - 8º 0.055 - 0.061 (1.40 - 1.55) 0.012 - 0.020 (0.30 - 0.51) 0.004 - 0.010 (0.10 - 0.26) 0.015 - 0.035 (0.38 - 0.89) 0.006 - 0.010 (0.15 - 0.26) SEATING PLANE ORDERING INFORMATION © Micro Linear 1998. PART NUMBER TEMPERATURE RANGE PACKAGE ML6633CS 0ºC to 70ºC 8-Pin SOIC (S08) ML6633IS –40ºC to 85ºC 8-Pin SOIC (S08) (Obolsete) is a registered trademark of Micro Linear Corporation. All other trademarks are the property of their respective owners. Products described herein may be covered by one or more of the following U.S. patents: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; 5,546,017; 5,559,470; 5,565,761; 5,592,128; 5,594,376; 5,652,479; 5,661,427; 5,663,874; 5,672,959; 5,689,167; 5,714,897; 5,717,798; 5,742,151; 5,747,977; 5,754,012; 5,757,174; 5,767,653; 5,777,514. Japan: 2,598,946; 2,619,299; 2,704,176. Other patents are pending. Micro Linear reserves the right to make changes to any product herein to improve reliability, function or design. Micro Linear does not assume any liability arising out of the application or use of any product described herein, neither does it convey any license under its patent right nor the rights of others. The circuits contained in this data sheet are offered as possible applications only. Micro Linear makes no warranties or representations as to whether the illustrated circuits infringe any intellectual property rights of others, and will accept no responsibility or liability for use of any application herein. The customer is urged to consult with appropriate legal counsel before deciding on a particular application. 5 2092 Concourse Drive San Jose, CA 95131 Tel: (408) 433-5200 Fax: (408) 432-0295 www.microlinear.com DS6633-01