LM6313N

LM6313 High Speed High Power Operational Amplifier February 1995 LM6313 High Speed High Power Operational Amplifier General Description The LM6313 is a high-speed high-power operational amplifier This operational amplifier features a 35 MHz small signal bandwidth and 250 V ms slew rate A compensation pin is included for adjusting the open loop bandwidth The input stage (A1) and output stage (A2) are pinned out separately and can be used independently The operational amplifier is designed for low impedance loads and will deliver g 300 mA The LM6313 has both overcurrent and thermal shutdown protection with an error flag to signal both these fault conditions These amplifiers are built with National’s VIPTM (Vertically Integrated PNP) process which provides fast PNP transistors that are true complements to the already fast NPN devices This advanced junction-isolated process delivers high speed performance without the need for complex and expensive dielectric isolation Features Y Y Y Y Y Y Y Y High slew rate 250 V ms Wide bandwidth 35 MHz g 300 mA Peak output current Input and output stages pinned out separately Single or dual supply operation Thermal protection Error flag warns of faults g 5V to g 15V Wide supply voltage range Applications Y Y Y Y Y Y High speed ATE pin driver Data acquisition Driving capacitive loads Flash A-D input driver Precision 50X –75X video line driver Laser diode driver Connection Diagram Dual-In-Line Package Typical Application TL H 10521 – 2 TL H 10521 – 1 Top View Order Number LM6313N See NS Package Number N16A Heat sink pins See Note 5 and Applications Do not ground or otherwise connect to this pin VIPTM is a trademark of National Semiconductor Corporation C1995 National Semiconductor Corporation TL H 10521 RRD-B30M75 Printed in U S A Absolute Maximum Ratings (Note 1) Total Supply Voltage ( a VS to bVS) A1 Differential Input Voltage (Note 2) A1 Input Voltage A2 Input to Output Voltage A2 Input Voltage Flag Output Voltage Short-Circuit to Ground Storage Temperature Range 36V ( g 18) g 7V Lead Temperature (Soldering 5 seconds) ESD Tolerance (Note 4) Pins 10 and 11 All Other Pins Operating Temperature Range LM6313N Thermal Derating Information (Note 5) iJA TJ (Max) 260 C g 600V g 1500V (V a b0 7) to (Vb b7V) g 7V g VS GND to a VS (Note 3) b 65 C s T s a 150 C 0 C to 70 C 40 C W 125 C Operational Amplifier DC Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes VCM e 0V RS e 50X the circuit configured as in Figure 1 Symbol VOS DVOS DT Ib IOS DIOS DT RIN CIN VCM AV1 AV2 CMRR PSRR VO1 VO2 VO3 IS Parameter Input Offset Voltage Average Input Offset Voltage Drift Input Bias Current Input Offset Current Average Input Offset Current Drift Input Resistance Input Capacitance Common-Mode Voltage Range Voltage Gain 1 Voltage Gain 2 Common-Mode Rejection Ratio Power Supply Rejection Ratio Output Voltage Swing 1 Output Voltage Swing 2 Output Voltage Swing 3 Supply Current RL e 1 kX VO e g 10V RL e 50X VO e g 8V b 10V s VCM s a 10V g 5V s VS s g 16V Conditions Typical 5 10 2 0 15 04 25 C Limit 20 0 C to 70 C Limit 22 Units mV (Max) mV C 5 15 7 19 mA (Max) mA (Max) nA C kX pF Differential AV e a 1 f e 10 MHz 325 22 a 14 2 b 13 2 a 13 8 b 12 8 a 13 7 b 12 7 V (Min) V V (Min) dB (Min) dB (Min) 6000 5000 90 90 13 1 12 0 11 0 18 300 2500 2000 72 72 11 8 10 5 90 23 2000 1500 70 70 11 2 10 0 85 24 RL e 1 kX RL e 100X RL e 50X TJ e 0 C TJ e 25 C TJ e 125 C (See Figure 3 ) g V (Min) mA (Max) 21 mA ISC Peak Short-Circuit Output TL H 10521 – 3 FIGURE 1 2 Electrical Characteristics (Continued) Operational Amplifier AC Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes VCM e 0V RS e 50X the circuit configured as in Figure 1 Symbol GBW SR PBW tS Parameter Gain-Bandwidth Product Slew Rate Power Bandwidth Settling Time Phase Margin Differential Gain Differential Phase en in Input Noise Voltage Input Noise Current f e 10 kHz f e 10 kHz Conditions f e 30 MHz AV e b1 RL e 50X (Note 6) VOUT e 20 VPP 10V Step to 0 1% (See Figure 2 ) AV e b1 RL e 1 kX CL e 50 pF Typical 35 250 30 200 53 01 01 14 18 Units MHz V ms MHz ns Deg % Deg nV pA SHz SHz A1 DC Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes VCM e 0V RS e 50X Symbol AVOL CMRR PSRR ISC Parameter Large Signal Voltage Gain Common-Mode Rejection Ratio Power Supply Rejection Ratio Output Short Circuit Current Conditions VOUT e g 10V RL e 2 kX VOUT e g 10V RL e % b 10V s VCM s a 10V g 5V s g VS s a 16V Typical 650 6000 90 90 g 60 25 C Limit 300 2500 72 72 g 30 0 C to 70 C Limit 250 2000 70 70 g 25 Units V V (Min) dB (Min) dB (Min) mA (Min) A1 AC Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes RS e 50X Symbol GBW SR Parameter Gain-Bandwidth Slew Rate Conditions f e 30 MHz AV e a 1 RL e 100 kX g 4 VIN g 2 VOUT Typical 37 250 25 C Limit 25 150 Units MHz (Min) V ms (Min) Note 1 Absolute Maximum Ratings indicate limits beyond which damage to the device may occur For guaranteed specifications and test conditions see the Electrical Characteristics The guaranteed specifications apply only for the test condition listed Some performance characteristics may degrade when the device is not operated under the listed test conditions Note 2 In order to achieve optimum AC performance the input stage was designed without protective clamps Exceeding the maximum differential input voltage results in reverse breakdown of the base-emitter junction of one of the input transistors Degradation of the input parameters (especially VOS IOS and Noise) is proportional to the level of the externally limited breakdown current and the accumulated duration of the breakdown condition Note 3 Continuous short-circuit operation of A1 at elevated temperature can result in exceeding the maximum allowed junction temperature of 125 C A2 contains current limit and thermal shutdown to protect against fault conditions The device may be damaged by shorts to the supplies Note 4 Human body model C e 100 pF RS e 1500X 3 Electrical Characteristics (Continued) A2 DC Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes RS e 50X Symbol AV1 AV2 VOS Ib RIN CIN RO VO Parameter Voltage Gain 1 Voltage Gain 2 Offset Voltage Input Bias Current Input Resistance Input Capacitance Output Resistance Voltage Output Swing IOUT e g 10 mA RL e 1 kX RL e 100X RL e 50X VS e g 5V to g 16V Conditions RL e 1 kX VIN e g 10V RL e 50X VIN e g 10V RL e 1 kX RL e 1 kX RS e 10 kX RL e 50X Typical 0 99 09 15 1 5 35 35 13 7 12 5 11 0 70 50 13 0 10 5 90 60 80 12 7 10 0 85 50 25 C Limit 0 97 0 85 70 6 0 C to 70 C Limit 0 95 0 82 100 8 Units V mV (Min) V V (Min) mV (Max) mA (Max) MX pF X (Min) V (Min) PSRR Power Supply Rejection Ratio dB (Min) A2 AC Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes RS e 50X Symbol SR 1 SR 2 BW tr tf PD Parameter Slew Rate 1 Slew Rate 2 b 3 dB Bandwidth Conditions VIN e g 11V RL e 1 kX VIN e g 11V RL e 50X (Note 7) VIN e g 100 mVpp RL e 50X CL s 10 pF RL e 1 kX CL s 10 pF VO e 100 mVpp RL e 50X CL s 10 pF VO e 100 mVpp RL e 1 kX CL e 100 pF RL e 50X CL e 1000 pF Typical 1200 750 65 8 4 13 21 25 C Limit 550 30 Units V ms (Min) MHz (Min) ns ns % Rise Time Fall Time Propagation Delay Overshoot Additional (A2) Electrical Characteristics Unless otherwise specified all limits guaranteed for TA e 25 C and Supply Voltage VS e g 15V Boldface limits apply at temperature extremes Symbol VOL IOH Parameter Flag Pin Output Low Voltage Flag Pin Output High Current Conditions ISINK Flag Pin e 500 mA VOH Flag Pin e 15V (Note 8) Typical 220 0 01 25 C Limit 340 10 0 C to 70 C Limit 400 20 Units mV (Max) mA (Max) Note 5 For operation at elevated temperature these devices must be derated to insure TJ s 125 C TJ e TA a (PD c iJA) iJA for the N package mounted flush to the PCB is 40 C W when pins 4 5 12 and 13 are soldered to a total of 2 in2 of copper trace Note 6 Measured between g 5V Note 7 VIN e g 9V step input measured between g 5V out Note 8 The error flag is set during current limit or thermal shut-down The flag is an open collector low on fault 4 Simplified Schematic TL H 10521 – 4 Settling Time Test Circuit TL H 10521 – 6 TL H 10521 – 5 FIGURE 3 FIGURE 2 Protection Circuit Block Diagram TL H 10521 – 7 5 Typical Performance Characteristics Op Amp (Unless otherwise specified TA e 25 C VS e g 15V and RL e 10 kX ) Slew Rate vs Capacitive Load Output Resistance (Open Loop) Bode Plot Bias Current vs Common-Mode Voltage Supply Current vs Supply Voltage Power Supply Rejection Input Noise Voltage Input Noise Current Slew Rate vs Compensation Gain-Bandwidth Phase Margin vs Comp Cap and Load Cap CMR vs Frequency GBW and Phase Margin vs Comp Cap TL H 10521 – 8 6 Typical Performance Characteristics A1 Only (Unless otherwise specified TA e 25 C VS e g 15V and RL e 10 kX ) Gain vs Supply Voltage Bode Plot Gain-Bandwidth and Phase Margin vs Load Capacity Output Saturation Voltage Common-Mode Input Saturation Voltage Output Resistance (Open Loop) TL H 10521 – 9 Typical Performance Characteristics A2 Only (Unless otherwise specified TA e 25 C and VS e g 15V ) Slew Rate vs Supply Voltage Slew Rate vs Input Amplitude Slew Rate vs Temperature Bandwidth vs Supply Voltage Overshoot vs Capacitive Load Gain and Phase Shift (RL e 50X) TL H 10521 – 10 7 Application Hints The LM6313 is a high-speed high power operational amplifier that is designed for driving low-impedance loads such as 50X and 75X cables Available in the standard low cost 16-pin DIP this amplifier will drive back terminated video cables with up to 10 Vp-p The ability to add additional compensation allows the LM6313 to drive capacitive loads of any size at bandwidths previously possible only with very expensive hybrid devices The LM6313 is excellent for driving high-speed flash A-to-D converters that require low-impedance drive at high frequencies At 1 MHz when used as a buffer the LM6313 output impedance is below 0 1X This very low output impedance also means that cables can be accurately backterminated by just placing the characteristic impedance in series with the LM6313 output OVER-VOLTAGE PROTECTION If the LM6313 is being operated on supply voltages of greater than g 5V the possibility of damaging the output stage transistors exists At higher supply voltages if the output is shorted or excessive power dissipation causes the output stage to shut down the maximum A2 input-to-output voltage can be exceeded This occurs when the input stage tries to drive the output while the output is at ground To prevent this from happening an easy solution is to place diodes around the output stage (See Figure 4 ) This will limit the maximum differential voltage to about 1 3V Any signal diode such as the 1N914 or the 1N4148 will work fine SUPPLY BYPASSING Because of the large currents required to drive low-impedance loads supply bypassing as close as possible to the I C is important At 50 MHz a few inches of wire or circuit trace can have 20X or 30X of inductive reactance This inductance in series with a 0 1 mF bypass capacitor can resonate at 1 MHz to 2 MHz and just appear as an inductor at higher frequencies A 0 1 mF and a 10mF to 15 mF capacitor connected in parallel and as close as possible to the LM6313 supply pins from each supply to ground will give best performance SELECTION OF COMPENSATION CAPACITOR The compensation pin pin 15 makes it possible to drive any load at any closed loop gain without stability problems In most cases where the gain is b1 or greater and the load is resistive no compensation capacitor is required When used at unity gain or when driving reactive loads a small capacitor of 5 pF to 20 pF will insure optimum performance The easiest way to determine the best value of compensation capacitor is to temporarily connect a trimmer capacitor (typical range of 2 pF to 15 pF) between pin 15 and ground and adjust it for little or no overshoot at the output while driving the input with a square wave If the actual load capacitance is known the typical graphs ‘‘Gain-Bandwidth and Phase Margin vs Load Capacitance’’ can be used to select a value VIDEO CABLE DRIVER The LM6313 is ideally suited for driving 50X or 75X cables Unlike a buffer that requires a separate gain stage to make up for the losses involved in termination the LM6313 gain can be set to 1 plus the line losses when the transmission line is end-terminated If back-termination is needed adding the line impedance in series with the output and raising the gain to 2 plus the expected line losses will provide a 0 dB loss system Figure 5 illustrates the back and end terminated video system including compensation for line losses The excellent stability of the LM6313 with changes in supply voltages allow running the amplifier on unregulated supplies The typical change in phase shift when the supplies are changed from g 5V to g 15V is less than 3 at 10 MHz TL H 10521 – 11 FIGURE 4 HEAT SINKING When driving a low impedance load such as 50X and operating from g 15V supplies the internal power dissipation of the LM6313 can rise above 3W To prevent overheating of the chip which would cause the thermal protection circuitry to shut the system down the following guidelines should be followed 1 Reduce the supply voltage The LM6313 will operate with little change in performance except output voltage swing on g 5V supplies This will reduce the dissipation to the level where no precautions against overheating are necessary for loads of 10X or more 2 Solder pins 4 5 12 and 13 to copper traces which are at least 0 100 inch wide and have a total area of at least 2 square inches to obtain a iJA of 40 C W These four pins are connected to the back of the chip and will be at Vb They should not be used as a Vb connection unless pin 3 is also connected to this same point TL H 10521 – 12 FIGURE 5 8 Application Hints (Continued) LASER DIODE MODULATOR Figure 6 is a minimum component count example of a video modulator for a CW laser diode This example biases the diode at 200 mA and modulates the current at g 200 mA per volt of signal If it is desired to reduce power consumption and g 5V supplies are available all that is necessary is to change R2 to 5 kX and R4 to 15X CAPACITIVE LOAD DRIVING Figure 7 is the circuit used to demonstrate the ability of the LM6313 to drive capacitive loads at speeds not previously possible with monolithic op amps TL H 10521 – 14 FIGURE 7 TL H 10521 – 13 FIGURE 6 In photo 1 CL is 1000 pF The LM6313 is slewing at 250 V ms from b5V to a 5V The slew rate is 450 V ms from a 5V to b5V This requires the op amp to deliver 450 mA into the load and remain stable In photo 2 CL is changed to 1 mF Under these conditions the op amp is forced into current limiting Here the current is internally limited to about g 400 mA Note the rapid and complete recovery to normal operation at the end of slewing TL H 10521 – 16 TL H 10521 – 15 Photo 1 Photo 2 9 LM6313 High Speed High Power Operational Amplifier Physical Dimensions inches (millimeters) Lit 108290 16-Lead Molded Dual-In-Line Package (N) Order Number LM6313N NS Package Number N16A LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION As used herein 1 Life support devices or systems are devices or systems which (a) are intended for surgical implant into the body or (b) support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user National Semiconductor Corporation 2900 Semiconductor Drive P O Box 58090 Santa Clara CA 95052-8090 Tel 1(800) 272-9959 TWX (910) 339-9240 National Semiconductor GmbH Livry-Gargan-Str 10 D-82256 F4urstenfeldbruck Germany Tel (81-41) 35-0 Telex 527649 Fax (81-41) 35-1 National Semiconductor Japan Ltd Sumitomo Chemical Engineering Center Bldg 7F 1-7-1 Nakase Mihama-Ku Chiba-City Ciba Prefecture 261 Tel (043) 299-2300 Fax (043) 299-2500 2 A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness National Semiconductor Hong Kong Ltd 13th Floor Straight Block Ocean Centre 5 Canton Rd Tsimshatsui Kowloon Hong Kong Tel (852) 2737-1600 Fax (852) 2736-9960 National Semiconductores Do Brazil Ltda Rue Deputado Lacorda Franco 120-3A Sao Paulo-SP Brazil 05418-000 Tel (55-11) 212-5066 Telex 391-1131931 NSBR BR Fax (55-11) 212-1181 National Semiconductor (Australia) Pty Ltd Building 16 Business Park Drive Monash Business Park Nottinghill Melbourne Victoria 3168 Australia Tel (3) 558-9999 Fax (3) 558-9998 National does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications