HS-1412RH Data Sheet Radiation Hardened, Quad, High Speed, Low Power, Video Closed Loop Buffer The HS-1412RH is a radiation hardened quad closed loop buffer featuring user programmable gain and high speed performance. Manufactured on Intersil’s proprietary complementary bipolar UHF-1 (DI bonded wafer) process, this device offers wide -3dB bandwidth of 340MHz, very fast slew rate, excellent gain flatness and high output current. These devices are QML approved and are processed and screened in full compliance with MIL-PRF-38535. A unique feature of the pinout allows the user to select a voltage gain of +1, -1, or +2, without the use of any external components. Gain selection is accomplished via connections to the inputs, as described in the “Application Information” section. The result is a more flexible product, fewer part types in inventory, and more efficient use of board space. Compatibility with existing op amp pinouts provides flexibility to upgrade low gain amplifiers, while decreasing component count. Unlike most buffers, the standard pinout provides an upgrade path should a higher closed loop gain be needed at a future date. Specifications for Rad Hard QML devices are controlled by the Defense Supply Center in Columbus (DSCC). The SMD numbers listed here must be used when ordering. Detailed Electrical Specifications for these devices are contained in SMD 5962-96834. A “hot-link” is provided on our homepage for downloading. www.intersil.com/spacedefense/space.asp August 1999 File Number 4230.1 Features • Electrically Screened to SMD # 5962-96834 • QML Qualified per MIL-PRF-38535 Requirements • MIL-PRF-38535 Class V Compliant • User Programmable For Closed-Loop Gains of +1, -1 or +2 Without Use of External Resistors • Standard Operational Amplifier Pinout • Low Supply Current . . . . . . . . . . . . 5.9mA/Op Amp (Typ) • Excellent Gain Accuracy . . . . . . . . . . . . . . . 0.99V/V (Typ) • Wide -3dB Bandwidth. . . . . . . . . . . . . . . . . .340MHz (Typ) • Fast Slew Rate . . . . . . . . . . . . . . . . . . . . . .1155V/µs (Typ) • High Input Impedance . . . . . . . . . . . . . . . . . . . 1MΩ (Typ) • Excellent Gain Flatness (to 50MHz). . . . . . ±0.02dB (Typ) • Fast Overdrive Recovery . . . . . . . . . . . . . . . . <10ns (Typ) • Total Gamma Dose. . . . . . . . . . . . . . . . . . . . 300kRAD(Si) • Latch Up . . . . . . . . . . . . . . . . . . . . . None (DI Technology) Applications • Flash A/D Driver • Video Switching and Routing • Pulse and Video Amplifiers • Wideband Amplifiers • RF/IF Signal Processing • Imaging Systems Ordering Information ORDERING NUMBER INTERNAL MKT. NUMBER TEMP. RANGE (oC) 5962F9683401VCA HS1-1412RH-Q -55 to 125 5962F9683401VCC HS1B-1412RH-Q -55 to 125 Pinout HS-1412RH (CERDIP) GDIP1-T14 OR HS-1412RH (SBDIP) CDIP2-T14 TOP VIEW OUT1 1 -IN1 2 13 -IN4 +IN1 3 12 +IN4 V+ 4 11 V- +IN2 5 10 +IN3 -IN2 6 9 -IN3 OUT2 7 1 14 OUT4 8 OUT3 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 321-724-7143 | Copyright © Intersil Corporation 1999 HS-1412RH Application Information Unity Gain Considerations HS-1412RH Advantages The HS-1412RH features a novel design which allows the user to select from three closed loop gains, without any external components. The result is a more flexible product, fewer part types in inventory, and more efficient use of board space. Implementing a quad, gain of 2, cable driver with this IC eliminates the eight gain setting resistors, which frees up board space for termination resistors. Like most newer high performance amplifiers, the HS-1412RH is a current feedback amplifier (CFA). CFAs offer high bandwidth and slew rate at low supply currents, but can be difficult to use because of their sensitivity to feedback capacitance and parasitics on the inverting input (summing node). The HS-1412RH eliminates these concerns by bringing the gain setting resistors on-chip. This yields the optimum placement and value of the feedback resistor, while minimizing feedback and summing node parasitics. Because there is no access to the summing node, the PCB parasitics do not impact performance at gains of +2 or -1 (see “Unity Gain Considerations” for discussion of parasitic impact on unity gain performance). The HS-1412RH’s closed loop gain implementation provides better gain accuracy, lower offset and output impedance, and better distortion compared with open loop buffers. Closed Loop Gain Selection This “buffer” operates in closed loop gains of -1, +1, or +2, with gain selection accomplished via connections to the ±inputs. Applying the input signal to +IN and floating -IN selects a gain of +1 (see next section for layout caveats), while grounding -IN selects a gain of +2. A gain of -1 is obtained by applying the input signal to -IN with +IN grounded through a 50Ω resistor. The table below summarizes these connections: CONNECTIONS GAIN (ACL) +INPUT -INPUT -1 50Ω to GND Input +1 Input NC (Floating) +2 Input GND Unity gain selection is accomplished by floating the -Input of the HS-1412RH. Anything that tends to short the -Input to GND, such as stray capacitance at high frequencies, will cause the amplifier gain to increase toward a gain of +2. The result is excessive high frequency peaking, and possible instability. Even the minimal amount of capacitance associated with attaching the -Input lead to the PCB results in approximately 6dB of gain peaking. At a minimum this requires due care to ensure the minimum capacitance at the -Input connection. Table 1 lists five alternate methods for configuring the HS-1412RH as a unity gain buffer, and the corresponding performance. The implementations vary in complexity and involve performance trade-offs. The easiest approach to implement is simply shorting the two input pins together, and applying the input signal to this common node. The amplifier bandwidth decreases from 550MHz to 370MHz, but excellent gain flatness is the benefit. A drawback to this approach is that the amplifier input noise voltage and input offset voltage terms see a gain of +2, resulting in higher noise and output offset voltages. Alternately, a 100pF capacitor between the inputs shorts them only at high frequencies, which prevents the increased output offset voltage but delivers less gain flatness. Another straightforward approach is to add a 620Ω resistor in series with the amplifier’s positive input. This resistor and the HS-1412RH input capacitance form a low pass filter which rolls off the signal bandwidth before gain peaking occurs. This configuration was employed to obtain the data sheet AC and transient parameters for a gain of +1. Pulse Overshoot The HS-1412RH utilizes a quasi-complementary output stage to achieve high output current while minimizing quiescent supply current. In this approach, a composite device replaces the traditional PNP pulldown transistor. The composite device switches modes after crossing 0V, resulting in added distortion for signals swinging below ground, and an increased overshoot on the negative portion of the output waveform (see Figure 5, Figure 7, and Figure 9). This overshoot isn’t present for small bipolar signals (see Figure 4, Figure 6, and Figure 8) or large positive signals. Figure 28 through Figure 31 illustrate the amplifier’s overshoot dependency on input transition time, and signal polarity. TABLE 1. UNITY GAIN PERFORMANCE FOR VARIOUS IMPLEMENTATIONS PEAKING (dB) BW (MHz) SR (V/µs) ±0.1dB GAIN FLATNESS (MHz) Remove -IN Pin 5.0 550 1300 18 +RS = 620Ω 1.0 230 1000 25 +RS = 620Ω and Remove -IN Pin 0.7 225 1000 28 Short +IN to -IN (e.g., Pins 2 and 3) 0.1 370 500 170 100pF Capacitor Between +IN and -IN 0.3 380 550 130 APPROACH 2 HS-1412RH PC Board Layout Evaluation Board This amplifier’s frequency response depends greatly on the care taken in designing the PC board (PCB). The use of low inductance components such as chip resistors and chip capacitors is strongly recommended, while a solid ground plane is a must! The performance of the HS-1412RH may be evaluated using the HA5025 Evaluation Board, slightly modified as follows: Attention should be given to decoupling the power supplies. A large value (10µF) tantalum in parallel with a small value (0.1µF) chip capacitor works well in most cases. Terminated microstrip signal lines are recommended at the input and output of the device. Capacitance directly on the output must be minimized, or isolated as discussed in the next section. An example of a good high frequency layout is the Evaluation Board shown in Figure 3. 1. Remove the four feedback resistors, and leave the connections open. 2. a. For AV = +1 evaluation, remove the gain setting resistors (R1), and leave pins 2, 6, 9, and 13 floating. b. For AV = +2, replace the gain setting resistors (R1) with 0Ω resistors to GND. The modified schematic for amplifier 1, and the board layout are shown in Figures 2 and 3. To order evaluation boards (part number HA5025EVAL), please contact your local sales office. 50Ω OUT R 1(NOTE) 1 2 Driving Capacitive Loads Capacitive loads, such as an A/D input, or an improperly terminated transmission line will degrade the amplifier’s phase margin resulting in frequency response peaking and possible oscillations. In most cases, the oscillation can be avoided by placing a resistor (RS) in series with the output prior to the capacitance. Figure 1 details starting points for the selection of this resistor. The points on the curve indicate the RS and CL combinations for the optimum bandwidth, stability, and settling time, but experimental fine tuning is recommended. Picking a point above or to the right of the curve yields an overdamped response, while points below or left of the curve indicate areas of underdamped performance. IN 3 50Ω 4 14 + 13 NOTE: R1 = ∞ (AV = +1) or 0Ω (AV = +2) 12 11 5 10 0.1µF 6 9 7 8 -5V 0.1µF +5V 10µF GND GND FIGURE 2. MODIFIED EVALUATION BOARD SCHEMATIC SERIES OUTPUT RESISTANCE (Ω) 50 40 30 20 AV = +1 FIGURE 3A. TOP LAYOUT AV = +2 10 0 0 50 100 150 200 250 300 350 400 LOAD CAPACITANCE (pF) FIGURE 1. RECOMMENDED SERIES RESISTOR vs LOAD CAPACITANCE RS and CL form a low pass network at the output, thus limiting system bandwidth well below the amplifier bandwidth of 350MHz. By decreasing RS as CL increases (as illustrated in the curves), the maximum bandwidth is obtained without sacrificing stability. In spite of this, bandwidth decreases as the load capacitance increases. For example, at AV = +2, RS = 22Ω, CL = 100pF, the overall bandwidth is 125MHz, and bandwidth drops to 100MHz at RS = 12Ω, CL = 220pF. 3 10µF FIGURE 3B. BOTTOM LAYOUT FIGURE 3. EVALUATION BOARD LAYOUT HS-1412RH Typical Performance Curves VSUPPLY = ±5V, TA = 25oC, RL = 100Ω, Unless Otherwise Specified 2.0 200 AV = +2 150 1.5 100 1.0 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (mV) AV = +2 50 0 -50 -100 -150 0.5 0 -0.5 -1.0 -1.5 -200 -2.0 TIME (5ns/DIV.) TIME (5ns/DIV.) FIGURE 4. SMALL SIGNAL PULSE RESPONSE FIGURE 5. LARGE SIGNAL PULSE RESPONSE 2.0 200 1.5 100 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (mV) 150 AV = +1 50 0 -50 -100 -150 AV = +1 1.0 0.5 0 -0.5 -1.0 -1.5 -2.0 -200 TIME (5ns/DIV.) TIME (5ns/DIV.) FIGURE 6. SMALL SIGNAL PULSE RESPONSE FIGURE 7. LARGE SIGNAL PULSE RESPONSE 2.0 200 AV = -1 150 1.5 100 1.0 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (mV) AV = -1 50 0 -50 -100 -150 0.5 0 -0.5 -1.0 -1.5 -200 -2.0 TIME (5ns/DIV.) FIGURE 8. SMALL SIGNAL PULSE RESPONSE 4 TIME (5ns/DIV.) FIGURE 9. LARGE SIGNAL PULSE RESPONSE HS-1412RH 9 3 AV = +2 GAIN AV = -1 AV = +1 AV = +2 PHASE 0 90 0.3 1 AV = -1 180 AV = +1 270 10 FREQUENCY (MHz) 100 0.3 GAIN (dB) 0 GAIN -3 RL = 1kΩ RL = 100Ω RL = 50Ω 0 90 1 10 FREQUENCY (MHz) 180 270 100 RL = 1kΩ RL =100Ω RL = 50Ω 180 90 0.3 1 10 FREQUENCY (MHz) 100 0 -90 500 FIGURE 13. FREQUENCY RESPONSE FOR VARIOUS LOAD RESISTORS AV = +1 GAIN GAIN (dB) 3 1VP-P 2.5VP-P 4VP-P 3 0 0 PHASE 90 1VP-P 2.5VP-P 4VP-P 1 10 FREQUENCY (MHz) 180 270 100 360 500 FIGURE 14. FREQUENCY RESPONSE FOR VARIOUS OUTPUT VOLTAGES 5 0 GAIN -3 1VP-P 2.5VP-P 4VP-P -6 PHASE (DEGREES) GAIN (dB) 500 GAIN -3 RL = 1kΩ RL = 100Ω RL = 50Ω AV = +2 0.3 100 PHASE 500 FIGURE 12. FREQUENCY RESPONSE FOR VARIOUS LOAD RESISTORS 6 10 FREQUENCY (MHz) 270 AV = -1, VOUT = 200mVP-P -6 PHASE 0.3 0 PHASE (DEGREES) GAIN (dB) 3 RL = 1kΩ RL = 100Ω RL = 50Ω 1 180 FIGURE 11. FREQUENCY RESPONSE FOR VARIOUS LOAD RESISTORS AV = +1, VOUT = 200mVP-P -6 90 RL = 1kΩ RL = 100Ω RL = 50Ω 500 FIGURE 10. FREQUENCY RESPONSE 0 PHASE PHASE (DEGREES) -6 9 RL = 1kΩ RL = 100Ω RL = 50Ω 0 -3 3 GAIN 3 0 PHASE 90 180 1VP-P 2.5VP-P 4VP-P 0.3 1 10 FREQUENCY (MHz) 270 100 360 500 PHASE (DEGREES) 0 6 AV = +2, VOUT = 200mVP-P PHASE (DEGREES) VOUT = 200mVP-P GAIN (dB) 6 VSUPPLY = ±5V, TA = 25oC, RL = 100Ω, Unless Otherwise Specified (Continued) PHASE (DEGREES) NORMALIZED GAIN (dB) Typical Performance Curves FIGURE 15. FREQUENCY RESPONSE FOR VARIOUS OUTPUT VOLTAGES HS-1412RH Typical Performance Curves 6 GAIN -3 1VP-P 2.5VP-P 4VP-P -6 180 1VP-P PHASE 90 4VP-P 2.5VP-P 0 -90 0.3 1 10 FREQUENCY (MHz) 100 NORMALIZED GAIN (dB) 0 AV = -1 PHASE (DEGREES) GAIN (dB) 3 VSUPPLY = ±5V, TA = 25oC, RL = 100Ω, Unless Otherwise Specified (Continued) VOUT = 5VP-P 3 0 -3 AV = +2 AV = +1 AV = -1 -6 -9 -12 -15 -18 -21 0.3 500 1 FIGURE 16. FREQUENCY RESPONSE FOR VARIOUS OUTPUT VOLTAGES 10 FREQUENCY (MHz) 100 500 FIGURE 17. FULL POWER BANDWIDTH 0.5 450 VOUT = 200mVP-P 0.4 NORMALIZED GAIN (dB) AV = +2 350 AV = -1 300 250 AV = +1 0.3 0.2 AV = +1 0.1 AV = +2 0 -0.1 -0.2 AV = -1 -0.3 -0.4 200 -50 -25 0 25 50 75 100 -0.5 125 TEMPERATURE (oC) 1 FIGURE 18. -3dB BANDWIDTH vs TEMPERATURE -40 0 -45 -10 -50 -20 CROSSTALK (dB) AV = +2 AV = -1 AV = +1 -60 -65 -70 -75 -50 -60 -90 100 FIGURE 20. REVERSE ISOLATION (S12) 6 500 RL = 100Ω RL = ∞ -70 -85 10 FREQUENCY (MHz) 200 -40 -80 1 100 -30 -80 -90 0.3 10 FREQUENCY (MHz) FIGURE 19. GAIN FLATNESS -55 GAIN (dB) BANDWIDTH (MHz) 400 0.3 1 10 FREQUENCY (MHz) FIGURE 21. ALL HOSTILE CROSSTALK 100 HS-1412RH Typical Performance Curves VSUPPLY = ±5V, TA = 25oC, RL = 100Ω, Unless Otherwise Specified (Continued) -40 -40 AV = +2 AV = +2 -45 20MHz -50 -50 DISTORTION (dBc) DISTORTION (dBc) -45 10MHz -55 -60 -65 -70 -60 10MHz -65 -70 -75 -75 -80 -5 20MHz -55 -80 -2 1 4 7 10 13 -5 -2 OUTPUT POWER (dBm) 1 4 7 10 13 OUTPUT POWER (dBm) FIGURE 22. 2nd HARMONIC DISTORTION vs POUT FIGURE 23. 3rd HARMONIC DISTORTION vs POUT -40 -40 AV = +1 AV = +1 -45 -45 20MHz -50 DISTORTION (dBc) DISTORTION (dBc) -50 -55 10MHz -60 -65 20MHz -55 -60 -70 -70 -75 -75 -80 -5 -80 -2 1 4 7 OUTPUT POWER (dBm) 10 13 -5 FIGURE 24. 2nd HARMONIC DISTORTION vs POUT -2 1 4 7 OUTPUT POWER (dBm) 10 13 FIGURE 25. 3rd HARMONIC DISTORTION vs POUT -40 -40 AV = -1 AV = -1 20MHz -45 -45 -50 -50 10MHz DISTORTION (dBc) DISTORTION (dBc) 10MHz -65 -55 -60 -65 -70 -75 20MHz -55 -60 10MHz -65 -70 -75 -80 -5 -80 -2 1 4 7 10 OUTPUT POWER (dBm) FIGURE 26. 2nd HARMONIC DISTORTION vs POUT 7 13 -5 -2 1 4 7 10 OUTPUT POWER (dBm) FIGURE 27. 3rd HARMONIC DISTORTION vs POUT 13 HS-1412RH Typical Performance Curves VSUPPLY = ±5V, TA = 25oC, RL = 100Ω, Unless Otherwise Specified (Continued) 20 20 VOUT = +1V VOUT = +0.5V 15 OVERSHOOT (%) OVERSHOOT (%) 15 10 AV = +1 10 AV = +1 5 5 0 100 500 AV = +2 AV = +2 AV = -1 900 1300 AV = -1 1700 0 100 2100 500 INPUT TRANSITION TIME (ps) 900 1300 2100 INPUT TRANSITION TIME (ps) FIGURE 28. OVERSHOOT vs TRANSITION TIME FIGURE 29. OVERSHOOT vs TRANSITION TIME 20 20 VOUT = 1VP-P VOUT = 0.5VP-P 15 10 AV = +2 AV = +1 AV = +2 15 AV = +1 OVERSHOOT (%) OVERSHOOT (%) 1700 AV = -1 10 5 5 AV = -1 0 100 500 900 1300 1700 0 100 2100 500 INPUT TRANSITION TIME (ps) 900 1300 1700 2100 INPUT TRANSITION TIME (ps) FIGURE 30. OVERSHOOT vs TRANSITION TIME FIGURE 31. OVERSHOOT vs TRANSITION TIME 0.02 AV = -1 0.2 AV = +2 ERROR (%) 0 -0.01 SETTLING ERROR (%) 0.01 AV = +1 -0.02 -0.03 AV = +2 -0.04 -0.05 -0.06 -1.5 0.1 0.05 0 -0.05 -0.1 -0.2 -1.0 -0.5 0 0.5 1.0 INPUT VOLTAGE (V) FIGURE 32. INTEGRAL LINEARITY ERROR 8 1.5 10 20 30 40 50 TIME (ns) 60 70 FIGURE 33. SETTLING RESPONSE 80 90 HS-1412RH VSUPPLY = ±5V, TA = 25oC, RL = 100Ω, Unless Otherwise Specified (Continued) 6.6 3.6 6.5 3.5 6.4 OUTPUT VOLTAGE (V) 6.3 6.2 6.1 6.0 5.9 5.8 +VOUT (RL= 100Ω) 3.3 3.2 |-VOUT| (RL= 50Ω) 3.1 +VOUT (RL= 50Ω) 3.0 2.9 2.8 5.7 2.7 5.6 2.6 5 5.5 6 SUPPLY VOLTAGE (±V) 6.5 7 -50 -25 0 FIGURE 34. SUPPLY CURRENT vs SUPPLY VOLTAGE 20 40 16 30 12 8 20 INI 4 ENI 0 0.1 1 10 FREQUENCY (kHz) 0 100 FIGURE 36. INPUT NOISE CHARACTERISTICS 9 50 75 100 FIGURE 35. OUTPUT VOLTAGE vs TEMPERATURE 50 10 25 TEMPERATURE (oC) NOISE CURRENT (pA/√Hz) 5.5 4.5 |-VOUT| (RL= 100Ω) AV = -1 3.4 NOISE VOLTAGE (nV/√Hz) SUPPLY CURRENT (mA/AMPLIFIER) Typical Performance Curves 125 HS-1412RH Burn-In Circuit HS-1412RH CERDIP 1 14 2 13 3 12 4 11 R1 D3 V+ D1 C1 R1 R1 D4 VR1 5 10 6 9 7 8 C2 D2 NOTES: 1. R1 = 1kΩ, ±5%, 1/4W [Per Socket]. 2. C1 = C2 = 0.01µF [Per Socket] or 0.1µF (Per Row) Minimum. 3. D1 = D2 = 1N4002 or Equivalent [Per Board]. 4. D3 = D4 = 1N4002 or Equivalent [Per Socket]. 5. (-V) + (+V) = 11V ±1.0V. 6. 20mA < (ICC, IEE) < 32mA. 7. -50mV < VOUT < +50mV. Irradiation Circuit HS-1412RH CERDIP 1 14 2 13 3 12 4 11 R1 V+ R1 R1 C1 VR1 5 10 6 9 7 8 C1 NOTES: 8. R1 = 1kΩ ±5% 9. C1 = 0.1µF 10. V+ = +5.0V ±0.5V 11. V- = -5.0V ±0.5V All Intersil semiconductor products are manufactured, assembled and tested under ISO9000 quality systems certification. Intersil semiconductor products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see web site http://www.intersil.com 10 HS-1412RH Die Characteristics DIE DIMENSIONS: ASSEMBLY RELATED INFORMATION: 79 mils x 118 mils x 19 mils (2000µm x 3000µm x 483µm) Substrate Potential (Powered Up): Floating (Recommend Connection to V-) INTERFACE MATERIALS: ADDITIONAL INFORMATION: Glassivation: Transistor Count: Type: Nitride Thickness: 4kÅ ±0.5kÅ 320 Top Metallization: Type: Metal 1: AICu(2%)/TiW Thickness: Metal 1: 8kÅ ±0.4kÅ Type: Metal 2: AICu(2%) Thickness: Thickness: Metal 2: 16kÅ ±0.8kÅ Substrate: UHF-1X. Bonded Wafer, DI Backside Finish: Silicon Metallization Mask Layout HS-1412RH -IN1 OUT1 OUT4 -IN4 +IN1 +IN4 V+ V- +IN2 +IN3 -IN2 11 OUT2 V- OUT3 -IN3