Dual 300MHz Current Feedback Amplifier Features General Description • 300MHz -3dB bandwidth • 4mA supply current (per amplifier) • Single and dual supply operation, from 5V to 10V • Single (EL5193C) and triple (EL5393C) available • High speed, 1GHz product available (EL5191C) • High speed, 6mA, 600MHz product available (EL5192C, EL5292C, and EL5392C The EL5293C is a dual current feedback amplifier with a bandwidth of 300MHz. This makes these amplifiers ideal for today’s high speed video and monitor applications. Applications Pin Configurations • • • • • • • • Battery-powered Equipment Hand-held, Portable Devices Video Amplifiers Cable Drivers RGB Amplifiers Test Equipment Instrumentation Current to Voltage Converters With a supply current of just 4mA per amplifier and the ability to run from a single supply voltage from 5V to 10V, these amplifiers are also ideal for hand held, portable or battery powered equipment. The EL5293C is offered in the industry standard 8-pin SO. The EL5293C operates over the industrial temperature range of -40°C to +85°C. 8-Pin SO OUTA 1 INA- 2 Ordering Information 8 VS+ + 7 OUTB INA+ 3 Package Tape & Reel EL5293CS 8-Pin SO - MDP0027 EL5293CS-T7 8-Pin SO 7” MDP0027 EL5293CS-T13 8-Pin SO 13” MDP0027 Part No EL5293C EL5293C Outline # VS- 4 6 INB+ 5 INB+ EL5293CS April 26, 2001 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. © 2001 Elantec Semiconductor, Inc. EL5293C EL5293C Dual 300MHz Current Feedback Amplifier Absolute Maximum Ratings (T A = 25°C) Values beyond absolute maximum ratings can cause the device to be prematurely damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. 11V Supply Voltage between VS+ and VSMaximum Continuous Output Current 50mA Operating Junction Temperature Power Dissipation Pin Voltages Storage Temperature Operating Temperature 125°C See Curves VS- - 0.5V to VS+ +0.5V -65°C to +150°C -40°C to +85°C Important Note: All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA. Electrical Characteristics VS+ = +5V, VS- = -5V, RF = 750Ω for AV = 1, RF = 375Ω for AV = 2, RL = 150Ω, TA = 25°C unless otherwise specified. Parameter Description Conditions Min Typ Max Unit AC Performance BW -3dB Bandwidth AV = +1 300 MHz AV = +2 200 MHz 20 MHz 2200 V/µs BW1 0.1dB Bandwidth SR Slew Rate VO = -2.5V to +2.5V, AV = +2 ts 0.1% Settling Time VOUT = -2.5V to +2.5V, AV = -1 12 ns CS Channel Separation f = 5MHz 60 dB en Input Voltage Noise 4.4 nV/√Hz in- IN- input current noise 17 pA/√Hz in+ IN+ input current noise dG Differential Gain Error dP Differential Phase Error   2000 50 pA/√Hz AV = +2 0.03 % AV = +2 0.04 ° DC Performance VOS Offset Voltage TCVOS Input Offset Voltage Temperature Coefficient ROL Transimpediance -10 Measured from TMIN to TMAX 1 10 mV 5 µV/°C 300 600 kΩ Input Characteristics CMIR Common Mode Input Range ±3 ±3.3 V CMRR Common Mode Rejection Ratio 42 50 dB +IIN + Input Current -60 1 60 µA -IIN - Input Current -35 1 35 µA RIN Input Resistance 45 kΩ CIN Input Capacitance 0.5 pF V Output Characteristics VO IOUT Output Voltage Swing RL = 150Ω to GND ±3.4 ±3.7 RL = 1kΩ to GND ±3.8 ±4.0 V Output Current RL = 10Ω to GND 95 120 mA Supply IsON Supply Current - Enabled (per amplifier) No Load, VIN = 0V 3 4 PSRR Power Supply Rejection Ratio DC, VS = ±4.75V to ±5.25V 55 75 -IPSR - Input Current Power Supply Rejection DC, VS = ±4.75V to ±5.25V -2 1. Standard NTSC test, AC signal amplitude = 286mVp-p, f = 3.58MHz 2 5 mA 2 µA/V dB Typical Performance Curves Non-Inverting Frequency Response (Phase) Non-Inverting Frequency Response (Gain) 90 6 AV=1 0 2 AV=2 AV=2 -2 Phase (°) Normalized Magnitude (dB) AV=1 AV=5 -6 -90 AV=5 -180 AV=10 AV=10 -270 -10 RF=750Ω RL=150Ω -14 1M RF=750Ω RL=150Ω 10M 100M -360 1M 1G 10M Inverting Frequency Response (Gain) 90 AV=-1 2 AV=-1 AV=-2 0 -2 Phase (°) Normalized Magnitude (dB) 1G Inverting Frequency Response (Phase) 6 AV=-3 -90 AV=-2 AV=-3 -180 -6 -10 -270 RF=500Ω RL=150Ω -14 1M RF=500Ω RL=150Ω 10M 100M -360 1M 1G 10M Frequency Response for Various CIN6 6 Normalized Magnitude (dB) 2pF added 1pF added 2 -2 -10 1M 1G Frequency Response for Various RL 10 -6 100M Frequency (Hz) Frequency (Hz) Normalized Magnitude (dB) 100M Frequency (Hz) Frequency (Hz) 0pF added AV=2 RF=500Ω RL=150Ω 100M -6 -14 1M 1G RL=150Ω RL=500Ω -2 -10 10M RL=100Ω 2 AV=2 RF=500Ω 10M 100M Frequency (Hz) Frequency (Hz) 3 1G EL5293C EL5293C Dual 300MHz Current Feedback Amplifier Dual 300MHz Current Feedback Amplifier Typical Performance Curves Frequency Response for Various CL Frequency Response for Various RF 6 AV=2 RL=150Ω RF=RG=500Ω 10 33pF 340Ω Normalized Magnitude (dB) Normalized Magnitude (dB) 14 22pF 6 15pF 2 8pF -2 10M 620Ω -2 750Ω -6 1.2kΩ AV=2 RG=RF RL=150Ω -10 100M -14 1M 1G 10M Frequency (Hz) 100M 1G Frequency (Hz) Frequency Response for Various Common-mode Input Voltages Group Delay vs Frequency 3.5 6 VCM=3V 3 Normalized Magnitude (dB) AV=2 RF=500Ω 2.5 Delay (ns) 475Ω 2 0pF -6 1M 2 1.5 AV=1 RF=750Ω 1 -2 VCM=-3V -6 AV=2 RF=500Ω RL=150Ω -10 0 1M 10M 100M -14 1M 1G VCM=0V 2 0.5 10M 100M 1G Frequency (Hz) Frequency (Hz) Transimpedance (ROL) vs Frequency PSRR and CMRR vs Frequency 20 10M 0 Phase PSRR+ 0 1M -180 10k Phase (°) 100k PSRR/CMRR (dB) -90 Magnitude (Ω) EL5293C EL5293C -270 Gain 1k -20 PSRR-40 CMRR -60 -360 100 1k 10k 100k 1M 10M Frequency (Hz) 100M -80 10k 1G 4 100k 1M 10M Frequency (Hz) 100M 1G Typical Performance Curves -3dB Bandwidth vs Supply Voltage for Inverting Gains -3dB Bandwidth vs Supply Voltage for Noninverting Gains 250 400 RF=750Ω RL=150Ω AV=1 200 300 -3dB Bandwidth (MHz) -3dB Bandwidth (MHz) 350 250 200 AV=2 150 AV=5 100 AV=-1 150 AV=-2 100 AV=-5 50 50 RF=500Ω RL=150Ω AV=10 0 5 0 7 6 8 9 5 10 6 7 9 10 Peaking vs Supply Voltage for Inverting Gains Peaking vs Supply Voltage for Non-inverting Gains 2.5 4 3.5 RF=750Ω RL=150Ω AV=1 RF=500Ω RL=150Ω 2 Peaking (dB) 3 Peaking (dB) 8 Total Supply Voltage (V) Total Supply Voltage (V) 2.5 2 1.5 AV=2 1 1.5 AV=-1 1 AV=-2 0.5 0.5 AV=10 0 5 6 7 8 9 0 5 10 6 7 -3dB Bandwidth vs Temperature for Non-inverting Gains AV=1 200 -3dB Bandwidth (MHz) -3dB Bandwidth (MHz) 400 300 0 -40 10 250 RF=750Ω RL=150Ω 100 9 -3dB Bandwidth vs Temperature for Inverting Gains 500 200 8 Total Supply Voltage (V) Total Supply Voltage (V) AV=2 AV=5 AV=-2 150 100 AV=-5 50 RF=500Ω RL=150Ω AV=10 10 AV=-1 60 110 0 -40 160 Ambient Temperature (°C) 10 60 Ambient Temperature (°C) 5 110 160 EL5293C EL5293C Dual 300MHz Current Feedback Amplifier Dual 300MHz Current Feedback Amplifier Typical Performance Curves Peaking vs Temperature Voltage and Current Noise vs Frequency 2.5 1000 RL=150Ω 2 Voltage Noise (nV/√Hz) , Current Noise (pA/√Hz) AV=1 Peaking (dB) 1.5 1 0.5 AV=-1 100 in+ in- 10 en 0 -0.5 -40 10 110 60 1 100 160 1000 10k 100k Frequency () Ambient Temperature (°C) 1M 10M Supply Current vs Supply Voltage 100 10 10 8 Supply Current (mA) Output Impedance (Ω) Closed Loop Output Impedance vs Frequency 1 0.1 0.01 6 4 2 0.001 100 0 1k 10k 100k 1M 10M 100M 1G 0 2 Frequency (Hz) 2nd and 3rd Harmonic Distortion vs Frequency 4 6 8 Supply Voltage (V) 10 12 Two-tone 3rd Order Input Referred Intermodulation Intercept (IIP3) -20 25 AV=+2 VOUT=2VP-P RL=100Ω 20 Input Power Intercept (dBm) -30 Harmonic Distortion (dBc) EL5293C EL5293C -40 2nd Order Distortion -50 -60 3rd Order Distortion -70 -80 15 10 5 0 -5 -90 1 10 -10 10 100 6 AV=+2 RL=150Ω AV=+2 RL=100Ω 100 Typical Performance Curves Differential Gain/Phase vs DC Input Voltage at 3.58MHz Differential Gain/Phase vs DC Input Voltage at 3.58MHz 0.03 0.04 AV=2 RF=RG=500Ω RL=150Ω dG (%) or dP (°) 0.01 dP AV=1 RF=750Ω RL=500Ω 0.03 0.02 0 dG (%) or dP (°) 0.02 dG -0.01 -0.02 0.01 dG 0 -0.01 -0.03 -0.02 -0.04 -0.03 -0.05 dP -0.04 -1 -0.5 0 0.5 1 -1 -0.5 DC Input Voltage 0 0.5 1 DC Input Voltage Output Voltage Swing vs Frequency THD<1% Output Voltage Swing vs Frequency THD<0.1% 10 10 8 8 Output Voltage Swing (VPP) Output Voltage Swing (VPP) RL=500Ω RL=150Ω 6 4 2 RL=500Ω 6 RL=150Ω 4 2 AV=2 AV=2 0 0 1 10 Frequency (MHz) 100 1 Small Signal Step Response 10 Frequency (MHz) 100 Large Signal Step Response VS=±5V RL=150Ω AV=2 RF=RG=500Ω VS=±5V RL=150Ω AV=2 RF=RG=500Ω 200mV/div 1V/div 10ns/div 10ns/div 7 EL5293C EL5293C Dual 300MHz Current Feedback Amplifier Dual 300MHz Current Feedback Amplifier Typical Performance Curves Settling Time vs Settling Accuracy Transimpedance (RoI) vs Temperature 25 625 AV=2 RF=RG=500Ω RL=150Ω VSTEP=5VP-P output 600 15 RoI (kΩ) Settling Time (ns) 20 10 575 550 5 0 0.01 0.1 525 -40 1 10 Settling Accuracy (%) 110 160 110 160 ICMR and IPSR vs Temperature 90 2 80 PSRR 1.5 ICMR/IPSR (µ A/V) 70 PSRR/CMRR (dB) 60 Die Temperature (°C) PSRR and CMRR vs Temperature 60 CMRR 50 40 30 ICMR+ 1 IPSR 0.5 ICMR- 0 20 10 -40 10 60 110 -0.5 -40 160 10 Die Temperature (°C) 60 Die Temperature (°C) Offset Voltage vs Temperature Input Current vs Temperature 2 60 40 Input Current (µ A) 1 VOS (mV) EL5293C EL5293C 0 20 IB0 IB+ -20 -1 -40 -2 -40 10 60 110 -60 -40 160 Die Temperature (°C) 10 60 Temperature (°C) 8 110 160 Typical Performance Curves Positive Input Resistance vs Temperature Supply Current vs Temperature 60 5 50 Supply Current (mA) 4 RIN+ (kΩ) 40 30 20 3 2 1 10 0 -40 10 60 110 0 -40 160 10 60 110 160 Temperature (°C) Temperature (°C) Positive Output Swing vs Temperature for Various Loads Negative Output Swing vs Temperature for Various Loads 4.2 -3.5 4.1 150Ω -3.6 4 -3.7 3.9 -3.8 VOUT (V) VOUT (V) 1kΩ 3.8 3.7 -3.9 -4 150Ω 1kΩ 3.6 -4.1 3.5 -40 10 60 110 -4.2 -40 160 10 Temperature (°C) 60 110 160 Temperature (°C) Output Current vs Temperature Slew Rate vs Temperature 130 4000 Sink Slew Rate (V/µ S) IOUT (mA) 125 Source 120 3500 3000 AV=2 RF=RG=500Ω RL=150Ω 115 -40 10 60 110 2500 -40 160 Die Temperature (°C) 10 60 Die Temperature (°C) 9 110 160 EL5293C EL5293C Dual 300MHz Current Feedback Amplifier Dual 300MHz Current Feedback Amplifier Typical Performance Curves Channel-to-Channel Isolation vs Frequency Package Power Dissipation vs Ambient Temp. JEDEC JESD51-3 Low Effective Thermal Conductivity Test Board 0 0.7 625mW 0.6 /W -60 0.5 C 0° 16 -40 8 SO Power Dissipation (W) -20 Gain (dB) EL5293C EL5293C 0.4 0.3 0.2 -80 0.1 -100 100k 0 1M 10M 100M 400M 0 Frequency (Hz) 25 50 75 100 Ambient Temperature (°C) 10 125 150 Pin Descriptions EL5293C 8-Pin SO Pin Name 1 OUTA Function Equivalent Circuit Output, channel A VS+ OUT VSCircuit 1 2 INA- Inverting input, channel A VS+ IN+ IN- VSCircuit2 3 INA+ 4 VS - Non-inverting input, channel A (See circuit 2) 5 INB+ Non-inverting input, channel B (See circuit 2) 6 INB- Inverting input, channel B (See circuit 2) 7 OUTB Output, channel B (See circuit 1) 8 VS + Negative supply Positive supply 11 EL5293C EL5293C Dual 300MHz Current Feedback Amplifier EL5293C EL5293C Dual 300MHz Current Feedback Amplifier Applications Information Product Description particularly for the SO package, should be avoided if possible. Sockets add parasitic inductance and capacitance which will result in additional peaking and overshoot. The EL5293C is a current-feedback operational amplifier that offers a wide -3dB bandwidth of 300MHz and a low supply current of 4mA per amplifier. The EL5293C works with supply voltages ranging from a single 5V to 10V and they are also capable of swinging to within 1V of either supply on the output. Because of their currentfeedback topology, the EL5293C does not have the normal gain-bandwidth product associated with voltagefeedback operational amplifiers. Instead, its -3dB bandwidth to remain relatively constant as closed-loop gain is increased. This combination of high bandwidth and low power, together with aggressive pricing make the EL5293C the ideal choice for many low-power/highbandwidth applications such as portable, handheld, or battery-powered equipment. Capacitance at the Inverting Input Any manufacturer’s high-speed voltage- or currentfeedback amplifier can be affected by stray capacitance at the inverting input. For inverting gains, this parasitic capacitance has little effect because the inverting input is a virtual ground, but for non-inverting gains, this capacitance (in conjunction with the feedback and gain resistors) creates a pole in the feedback path of the amplifier. This pole, if low enough in frequency, has the same destabilizing effect as a zero in the forward openloop response. The use of large-value feedback and gain resistors exacerbates the problem by further lowering the pole frequency (increasing the possibility of oscillation.) For varying bandwidth needs, consider the EL5191C with 1GHz on a 9mA supply current or the EL5192C with 600MHz on a 6mA supply current. Versions include single, dual, and triple amp packages with 5-pin SOT23, 16-pin QSOP, and 8-pin or 16-pin SO outlines. The EL5293C has been optimized with a 475Ω feedback resistor. With the high bandwidth of these amplifiers, these resistor values might cause stability problems when combined with parasitic capacitance, thus ground plane is not recommended around the inverting input pin of the amplifier. Power Supply Bypassing and Printed Circuit Board Layout As with any high frequency device, good printed circuit board layout is necessary for optimum performance. Low impedance ground plane construction is essential. Surface mount components are recommended, but if leaded components are used, lead lengths should be as short as possible. The power supply pins must be well bypassed to reduce the risk of oscillation. The combination of a 4.7µF tantalum capacitor in parallel with a 0.01µF capacitor has been shown to work well when placed at each supply pin. Feedback Resistor Values The EL5293C has been designed and specified at a gain of +2 with RF approximately 500Ω. This value of feedback resistor gives 200MHz of -3dB bandwidth at AV=2 with 2dB of peaking. With AV=-2, an RF of approximately 500Ω gives 175MHz of bandwidth with 0.2dB of peaking. Since the EL5293C is a current-feedback amplifier, it is also possible to change the value of RF to get more bandwidth. As seen in the curve of Frequency Response for Various RF and RG, bandwidth and peaking can be easily modified by varying the value of the feedback resistor. For good AC performance, parasitic capacitance should be kept to a minimum, especially at the inverting input. (See the Capacitance at the Inverting Input section) Even when ground plane construction is used, it should be removed from the area near the inverting input to minimize any stray capacitance at that node. Carbon or Metal-Film resistors are acceptable with the Metal-Film resistors giving slightly less peaking and bandwidth because of additional series inductance. Use of sockets, Because the EL5293C is a current-feedback amplifier, its gain-bandwidth product is not a constant for different closed-loop gains. This feature actually allows the EL5293C to maintain about the same -3dB bandwidth. As gain is increased, bandwidth decreases slightly while 12 stability increases. Since the loop stability is improving with higher closed-loop gains, it becomes possible to reduce the value of RF below the specified 475Ω and still retain stability, resulting in only a slight loss of bandwidth with increased closed-loop gain. Video performance has also been measured with a 500Ω load at a gain of +1. Under these conditions, the EL5293C has dG and dP specifications of 0.03% and 0.04°. Output Drive Capability Supply Voltage Range and Single-Supply Operation In spite of its low 4mA of supply current, the EL5293C is capable of providing a minimum of ±95mA of output current. With a minimum of ±95mA of output drive, the EL5293C is capable of driving 50Ω loads to both rails, making it an excellent choice for driving isolation transformers in telecommunications applications. The EL5293C has been designed to operate with supply voltages having a span of greater than 5V and less than 10V. In practical terms, this means that the EL5293C will operate on dual supplies ranging from ±2.5V to ±5V. With single-supply, the EL5293C will operate from 5V to 10V. Driving Cables and Capacitive Loads When used as a cable driver, double termination is always recommended for reflection-free performance. For those applications, the back-termination series resistor will decouple the EL5293C from the cable and allow extensive capacitive drive. However, other applications may have high capacitive loads without a back-termination resistor. In these applications, a small series resistor (usually between 5Ω and 50Ω) can be placed in series with the output to eliminate most peaking. The gain resistor (RG) can then be chosen to make up for any gain loss which may be created by this additional resistor at the output. In many cases it is also possible to simply increase the value of the feedback resistor (RF) to reduce the peaking. As supply voltages continue to decrease, it becomes necessary to provide input and output voltage ranges that can get as close as possible to the supply voltages. The EL5293C has an input range which extends to within 2V of either supply. So, for example, on +5V supplies, the EL5293C has an input range which spans ±3V. The output range of the EL5293C is also quite large, extending to within 1V of the supply rail. On a ±5V supply, the output is therefore capable of swinging from -----4V to +4V. Single-supply output range is larger because of the increased negative swing due to the external pull-down resistor to ground. Video Performance For good video performance, an amplifier is required to maintain the same output impedance and the same frequency response as DC levels are changed at the output. This is especially difficult when driving a standard video load of 150Ω, because of the change in output current with DC level. Previously, good differential gain could only be achieved by running high idle currents through the output transistors (to reduce variations in output impedance.) These currents were typically comparable to the entire 4mA supply current of each EL5293C amplifier. Special circuitry has been incorporated in the EL5293C to reduce the variation of output impedance with current output. This results in dG and dP specifications of 0.03% and 0.04°, while driving 150Ω at a gain of 2. Current Limiting The EL5293C has no internal current-limiting circuitry. If the output is shorted, it is possible to exceed the Absolute Maximum Rating for output current or power dissipation, potentially resulting in the destruction of the device. Power Dissipation With the high output drive capability of the EL5293C, it is possible to exceed the 125°C Absolute Maximum junction temperature under certain very high load current conditions. Generally speaking when RL falls below about 25Ω, it is important to calculate the maximum junction temperature (TJMAX ) for the application to determine if power supply voltages, load conditions, or package type need to be modified for the EL5293C to 13 EL5293C EL5293C Dual 300MHz Current Feedback Amplifier EL5293C EL5293C Dual 300MHz Current Feedback Amplifier remain in the safe operating area. These parameters are calculated as follows: T JMA X = T MA X + ( θ JA × n × PD MA X ) where: 70$; 0D[LPXP$PELHQW7HPSHUDWXUH θ-$ 7KHUPDO5HVLVWDQFHRIWKH3DFNDJH Q 1XPEHURI$PSOLILHUVLQWKH3DFNDJH 3'0$; 0D[LPXP3RZHU'LVVLSDWLRQRI(DFK $PSOLILHULQWKH3DFNDJH PDMAX for each amplifier can be calculated as follows: V OU T MAX PD MA X = ( 2 × V S × I SMA X ) + ( V S – V OU T MAX ) × ---------------------------RL where: 96 6XSSO\9ROWDJH ,60$; 0D[LPXP6XSSO\&XUUHQWRI$ 92870$; 0D[LPXP2XWSXW9ROWDJH5HTXLUHG 5/ /RDG5HVLVWDQFH 14 EL5293C EL5293C Dual 300MHz Current Feedback 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. April 26, 2001 WARNING - 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 Semiconductor, Inc. 675 Trade Zone Blvd. Milpitas, CA 95035 Telephone: (408) 945-1323 (888) ELANTEC Fax: (408) 945-9305 European Office: +44-118-977-6020 Japan Technical Center: +81-45-682-5820 15 Printed in U.S.A.