Fast Buffer Amplifier Features General Description # # # # # # The ELH0033 is a high-speed, FET input voltage follower buffer designed to provide high output currents from DC to over 100 MHz. The ELH0033 slews at 1500 V/ms and will drive 100X loads. Phase linearity is excellent to 20 MHz, allowing the buffer to be included in op amp loops. Slew rateÐ1500 V/ms Output driveÐ100 mA Rise and fall timesÐ2.9 ns Input resistanceÐ1011X Power bandwidthÐ100 MHz MIL-STD-883 devices 100% manufactured in U.S.A. Advantages # Excellent phase linearity # Driver cables and other capacitive loads # Wide supply range, single or split The ELH0033 is intended to fulfill a wide range of buffer applications such as high-speed line drivers, video impedance transformation, nuclear instrumentation amplifiers, op amp isolation buffers for driving reactive loads and high impedance input buffers for high-speed A to D’s and comparators. ELH0033G/883/8001401ZX ELH0033G/883/8001401ZX These devices are constructed using specially selected junction FETs and active laser trimming to achieve guaranteed performance specifications. The ELH0033 is specified for operation from b 55§ C to a 125§ C. Ordering Information Part No. Temp. Range Package OutlineÝ ELH0033G/883B b 55§ C to a 125§ C TO-8 MDP0002 8001401ZX is the SMD version of this device. Connection Diagram Elantec facilities comply with MIL-I-45208A and other applicable quality specifications. Elantec’s Military devices are 100% fabricated and assembled in our rigidly controlled, ultra-clean facilities in Milpitas, California. For additional information on Elantec’s Quality and Reliability Assurance policy and procedures request brochure QRA-1. 12-Pin TO-8 Equivalent Schematic 0033 – 1 Top View Note: Case is electrically isolated. Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a ‘‘controlled document’’. Current revisions, if any, to these specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation. Patent pending. © 1989 Elantec, Inc. July 1992 Rev H 0033 – 2 ELH0033G/883/8001401ZX Fast Buffer Amplifier Absolute Maximum Ratings VS VIN PD IOC IOP Supply Voltage (V a b Vb) Input Voltage Power Dissipation (See Curves) Continuous Output Current Peak Output Current 40V 40V 1.5W g 100 mA g 250 mA TA TJ TST Operating Temperature Range ELH0033 Operating Junction Temperature Storage Temperature Lead Temperature (Soldering, 10 seconds) b 55§ C to a 125§ C 175§ C b 65§ C to a 150§ C 300§ C Important Note: All parameters having Min/Max specifications are guaranteed. The Test Level column indicates the specific device testing actually performed during production and Quality inspection. Elantec performs most electrical tests using modern high-speed automatic test equipment, specifically the LTX77 Series system. Unless otherwise noted, all tests are pulsed tests, therefore TJ e TC e TA. Test Level I II III IV V Test Procedure 100% production tested and QA sample tested per QA test plan QCX0002. 100% production tested at TA e 25§ C and QA sample tested at TA e 25§ C , TMAX and TMIN per QA test plan QCX0002. QA sample tested per QA test plan QCX0002. Parameter is guaranteed (but not tested) by Design and Characterization Data. Parameter is typical value at TA e 25§ C for information purposes only. DC Electrical Characteristics VS e g 15V, VIN e 0V, TMIN s TA s TMAX Description VOS Output Offset Voltage DVOS/DT Average Temperature Coefficient of Offset Voltage Test Conditions Min RS s 100 kX, TJ e 25§ C (Note 1) Typ Max Test Level Units 5 10 I mV 15 I mV V mV/§ C RS s 100 kX IB AV RIN Input Bias Current RS e 100X 50 TJ e 25§ C (Note 1) 250 I pA TA e 25§ C (Note 2) 2.5 IV nA TJ e TA e TMAX 10 I nA 1.00 I V/V Voltage Gain RS e 100X, RL e 1 kX, VIN e g 10V 0.97 0.98 Input Impedance RL e 1 kX 1010 1011 IV X TJ e 25§ C (Note 1), RL e 1 kX 1010 1011 I X I X RO Output Impedance RL e 1 kX, VIN e g 1V VO Output Voltage Swing VIN e g 14V, RL e 1 kX g 12 I V VIN e g 10.5V, RL e 100X, TA e 25§ C g9 I V IS Supply Current 6 14.5 Power Consumption 10 20 22 I mA 600 660 I mW Note 1: Specification is at 25§ C junction temperature due to requirements of high-speed automatic testing. Actual values at operating temperature will exceed the value at TJ e 25§ C. When supply voltages are g 15V, no-load operating junction temperature may rise 40§ C– 60§ C above ambient and more under load conditions. Accordingly, VOS may change one to several mV, and IB will change significantly during warm-up. Refer to IB vs temperature graph for expected values. Note 2: Measured in still air 7 minutes after application of power. 2 TD is 3.4in ELH0033 Parameter ELH0033G/883/8001401ZX Fast Buffer Amplifier AC Electrical Characteristics TC e 25§ C, VS e g 15V, RS e 50X, RL e 1 kX Description Test Conditions Test Level Units 1500 III V/ms 100 V MHz 2 V § ns Min Typ 1000 Max SR Slew Rate VIN e g 10V BW Bandwidth VIN e 1 Vrms Phase Non-Linearity BW e 1 MHz to 20 MHz tr Rise Time DVIN e 0.5V 2.9 V tp Propagation Delay DVIN e 0.5V 1.2 V ns HD Harmonic Distortion f l 1 kHz k 0.1 V % AV Voltage Gain RS e 100X, VIN e 1 Vrms, f e 1 kHz RO Output Impedance 0.97 VIN e 1 Vrms, f e 1 kHz 0.98 1.00 I V/V 6 10 I X Typical Performance Curves Maximum Power Dissipation Supply Current vs Supply Voltage Output Voltage vs Supply Voltage Negative Pulse Response Positive Pulse Response Frequency Response 0033 – 3 3 TD is 2.3in ELH0033 Parameter ELH0033G/883/8001401ZX Fast Buffer Amplifier Typical Performance Curves Ð Contd. Rise and Fall Time vs Temperature Input Bias Current vs Temperature Normalized Input Bias Current During Warm-up Input Bias Current vs Input Voltage 0033 – 4 Typical Applications Offset Zero Adjust Using Resistor Current Limiting Current Limiting Using Current Sources 0033 – 5 0033 – 6 4 0033 – 7 ELH0033G/883/8001401ZX Fast Buffer Amplifier Typical Applications Ð Contd. High Input Impedance AC Coupled Amplifier Coaxial Cable Driver fH t 100 MHz 0033 – 9 *Select C1 for optimum pulse response 0033 – 8 Instrumentation Shield/Line Driver 0033 – 10 Single Supply AC Amplifier 4.5 MHz Notch Filter 1 2qR1C1 R1 e 2 R2 C2 C1 e 2 FO e 0033 – 11 0033 – 12 High-Speed Sample and Hold *Polycarbon or teflon 0033 – 13 5 ELH0033G/883/8001401ZX Fast Buffer Amplifier Short Circuit Protection Applications Information In order to optimize transient response and output swing, output current limit has been omitted from the ELH0033. Short circuit protection may be added by inserting appropriate value resistors between V a and VC a pins and V b and VC b pins. Resistor values may be predicted by: Recommended Layout Precautions RF/video printed circuit board layout rules should be followed when using the ELH0033 since it will provide power gain to frequencies over 100 MHz. Ground planes are recommended and power supplies should be decoupled at each device with low inductance capacitors. In addition, ground plane shielding may be extended to the metal case of the device since it is electrically isolated from internal circuitry. Alternatively, the case should be connected to the output to minimize input capacitance. RLIM j Va Vb e ISC ISC where: ISC s 100 mA for ELH0033 The inclusion of limiting resistors in the collectors of the output transistors reduces output voltage swing. Decoupling VC a and VC b pins with capacitors to ground will retain full output swing for transient pulses. An alternate active current limit technique that retains full DC output swing uses current sources which are saturated during normal operation thus applying full supply voltage to the VC pins. Under fault conditions, the voltage decreases as required by the overload. Offset Voltage Adjustment The ELH0033’s offset voltages have been actively trimmed by laser to meet guaranteed specifications when the offset preset pin is shorted to the offset adjust pin. The pre-calibration allows the devices to be used in most DC or AC applications without individually offset nulling each device. If offset null is desirable, it is simply obtained by leaving the offset preset pin open and connecting a trim pot of 100X between the offset adjust pin and V b . RLIM j VBE 0.6V e e 10X ISC 60 mA Operation from Single or Asymmetrical Power Supplies Capacitive Loading This device type may be readily used in applications where symmetrical supplies are unavailable or not desirable. A typical application might be an interface to a MOS shift register where V a e a 5V and V b e b 12V. In this case, an apparent output offset occurs due to the device’s voltage gain of less than unity. This additional output offset error may be predicted by: Thus: DVO j (1 b AV) The ELH0033 is designed to drive capacitive loads such as coaxial cables in excess of several thousand picofarads without susceptibility to oscillation. However, peak current resulting from (C c dv/dt) should be limited below absolute maximum peak current ratings for the devices. DVIN c CL s IOUT s g 250 mA Dt (V a b V b ) e 0.005 (V a b V b ) 2 In addition, power dissipation resulting from driving capacitive loads plus standby power should be kept below the total package power rating: where: AV e No load voltage gain, typically 0.99 V a e Positive supply voltage V b e Negative supply voltage For the above example, DVO would be b 35 mV. This may be adjusted to zero as described in Section 2. For AC coupled applications, no additional offset occurs if the DC input is properly biased as illustrated in the ‘‘typical applications’’ section. PD pkg t PDC a PAC PD pkg t (V a b V b ) c IS a PAC PAC j (VP-P)2 c f c CL 6 ELH0033G/883/8001401ZX Fast Buffer Amplifier where: VP-P e Peak-to-peak output voltage swing e Frequency f CL e Load Capacitance Hardware In order to utilize the full drive capabilities of the ELH0033, it should be mounted with a heatsink, particularly for extended temperature operation. The case is isolated from the circuit and may be connected to system chassis. Operation within an Op Amp Loop Both devices may be used as a current booster or isolation buffer within a closed loop with op amps such as the ELH0032 and HA2500 and HA2600 series. An isolation resistor of 47X should be used between the op amp output and the input of ELH0033. The wide bandwidth and high slew rates of the ELH0033 assure that the loop has the characteristics of the op amp and that additional rolloff is not required. IMPORTANT! Power supply bypassing is necessary to prevent oscillation with the ELH0033 in all circuits. Low inductance ceramic disc capacitors with the shortest practical lead lengths must be connected from each supply lead (within (/4× to (/2× of the device package) to a ground plane. Capacitors should be one or two 0.1mF in parallel; adding a 4.7 mF solid tantalum capacitor will help in troublesome instances. Burn-In Circuit 0033 – 14 7 ELH0033G/883/8001401ZX TAB WIDE Fast Buffer Amplifier ELH0033 Macromodel input l l l l l l Va l l l l l Vc a l l l l Vb l Vcb * output l l * l l l .subckt M0033 5 12 1 10 9 11 * Models .model qn npn (is e 5eb14 bf e 150 vaf e 100 re e 1 rb e 5 re e 1 ikf e 200mA a cje e 5pF cjc e 5pF mje e .42 mjc e .23 tf e .3nS tr e 200nS br e 5 vtf e 0) .model qp pnp (is e 5eb14 bf e 150 vaf e 100 rc e .2 rb e 3 re e 1 ikf e 100mA a cje e 5.7pF cjc e 4pF tf e .3nS mje e .32 mjc e .43 tr e 170nS br e 5 vtf e 0) .model qf njf (vto eb3V beta e 4.0eb3 cgd e 4pF cgs e 10pF lambda e 671.0eb6) * Resistors r1 20 21 58.33 r2 27 10 58.33 r3 22 11 2 r4 11 23 2 * Transistors j1 12 5 20 qf j4 24 10 26 qf q2 21 21 25 qn q3 24 24 25 qp q5 1 21 22 qn q6 9 24 23 qp q7 26 26 27 qn .ends 8 TD is 3.8in * Connections: * * * * ELH0033G/883/8001401ZX Fast Buffer Amplifier ELH0033 Macromodel Ð Contd. 0033 – 16 9 10 BLANK 11 BLANK ELH0033G/883/8001401ZX ELH0033G/883/8001401ZX Fast Buffer Amplifier General Disclaimer Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the circuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. July 1992 Rev H WARNING Ð Life Support Policy Elantec, Inc. products are not authorized for and should not be used within Life Support Systems without the specific written consent of Elantec, Inc. Life Support systems are equipment intended to support or sustain life and whose failure to perform when properly used in accordance with instructions provided can be reasonably expected to result in significant personal injury or death. Users contemplating application of Elantec, Inc. products in Life Support Systems are requested to contact Elantec, Inc. factory headquarters to establish suitable terms & conditions for these applications. Elantec, Inc.’s warranty is limited to replacement of defective components and does not cover injury to persons or property or other consequential damages. Elantec, Inc. 1996 Tarob Court Milpitas, CA 95035 Telephone: (408) 945-1323 (800) 333-6314 Fax: (408) 945-9305 European Office: 44-71-482-4596 12 Printed in U.S.A.