EL4453C EL4453C Video Fader Features General Description # Complete two-input fader with output amplifierÐuses no extra components # 80 MHz bandwidth # Fast fade control speed # Operates on g 5V to g 15V supplies # l 60 dB attenuation @ 5 MHz The EL4453C is a complete fader subsystem. It variably blends two inputs together for such applications as video picture-inpicture effects. The EL4453C operates on g 5V to g 15V supplies and has an analog differential input range of g 2V. AC characteristics do not change appreciably over the supply range. The circuit has an operational temperature of b 40§ C to a 85§ C and is packaged in 14-pin P-DIP and SO-14. Applications # # # # The EL4453C is fabricated with Elantec’s proprietary complementary bipolar process which gives excellent signal symmetry and is free from latch up. Mixing two inputs Picture-in-picture Text overlay onto video General gain control Connection Diagram Ordering Information Part No. Temp. Range Pkg. Outline Ý EL4453CN b 40§ C to a 85§ C 14-Pin P-DIP MDP0031 EL4453CS b 40§ C to a 85§ C 14-Lead SOIC MDP0027 4453 – 1 January 1995 Rev A 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. © 1995 Elantec, Inc. EL4453C Video Fader Absolute Maximum Ratings TA e 25§ C Va VS VIN DVIN Positive Supply Voltage V a to Vb Supply Voltage Voltage at any Input or Feedback Difference between Pairs of Inputs or Feedback IIN IOUT PD TA TS 16.5V 33V V a to Vb 6V Current into any Input, or Feedback Pin 4 mA Output Current 30 mA Maximum Power Dissipation See Curves b 40§ C to a 85§ C Operating Temperature Range b 60§ C to a 150§ C Storage Temperature Range 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. Open-Loop DC Electrical Characteristics Power Supplies at g 5V, Sum a e Sumb e 0, TA e 25§ C Description VDIFF VINA, VINB, or Sum Differential Input VoltageÐ Clipping 0.2% Nonlinearity VCM Common-Mode Range (All Inputs; VDIFF e 0) VS e g 5V VS e g 15V VOS A or B Input Offset Voltage VFADE, 100% Extrapolated Voltage for 100% Gain for VINA VFADE, 0% Extrapolated Voltage for 0% Gain for VINA IB Input Bias Current (All Inputs) with all VIN e 0 IOS Input Offset Current between VINA a and VINAb, VINB a and VINBb, Fade a and Fadeb, and Sum a and Sumb Typ 1.8 2.0 0.7 I V V V g 2.5 g 12.5 g 2.8 g 12.8 I I V V 25 I mV 0.9 1.05 1.2 I V b 1.2 FT VINA Signal Feedthrough, VFADE e b1.5V NL A or B Input Nonlinearity, VIN between a 1V and b1V, VINA or VINB Sum Input Max Test Units Level Min b 1.15 b 0.9 I V 9 20 I mA 0.2 4 I mA b 100 b 60 I dB 0.2 0.5 0.5 I V % % RIN, Signal Input Resistance, A, B, or Sum Input 230 V kX RIN, Fade Input Resistance, Fade Input 120 V kX CMRR Common-Mode Rejection Ratio, VINA or VINB 70 80 I dB PSRR Power Supply Rejection Ratio 50 70 I dB EG Gain Error, VFADE e 1.5V, VINA or VINB Sum Input b2 b4 I I % % VO Output Voltage Swing (VIN e 0, VREF Varied) VS e g 5V VS e g 15V I I V V ISC Output Short-Circuit Current IS Supply Current, VS e g 15V g 2.5 g 12.5 40 a2 a4 g 2.8 g 12.8 85 17 2 21 I mA I mA TD is 4.3in Parameter EL4453C Video Fader Closed-Loop AC Electrical Characteristics Parameter BW, b3 dB Description Min b 3 dB Small-Signal Bandwidth, VINA or VINB Test Level Units 80 V MHz MHz Typ Max BW, g 0.1 dB 0.1 dB Flatness Bandwidth, VINA or VINB 9 V Peaking Frequency Response Peaking 1.0 V dB BW, Fade b 3 dB Small-Signal Bandwidth, Fade Input 80 V MHz SR Slew Rate, VOUT between b2V and a 2V 380 I V/ms VN Input-Referred Noise Voltage Density 160 V nV/Hz FT Feedthrough of Faded-Out Channel, F e 3.58 MHz b 63 V dB dG Differential Gain Error, VOFFSET from 0 to g 0.714V, Fade at 100% VINA or VINB Sum Input 0.05 0.35 V V % % Differential Phase Error, VOFFSET from 0 to g 0.71V, Fade at 100% VINA or VINB Sum Input 0.05 0.1 V V (§ ) (§ ) di TBD Test Circuit 4453 – 2 Note: For typical performance curves Sum a e Sumb e 0, RF e 0X, RG e % , VFADE e a 1.5V, and CL e 15 pF, unless otherwise noted. 3 TD is 2.5in Power supplies at g 12V, TA e 25§ C, RL e 500X, CL e 15 pF, VFADE e 1.5V, Sum a e Sumb e 0 EL4453C Video Fader Typical Performance Curves Frequency Response Frequency Response vs Gain 4453 – 4 4453 – 3 Frequency Response for Various Loads, VS e g 5V Frequency Response for Various Loads, VS e g 15V 4453 – 6 4453 – 7 b 3 dB Bandwidth and Peaking b 3 dB Bandwidth and Peaking vs Supply Voltage vs Die Temperature 4453 – 10 4453 – 9 4 EL4453C Video Fader Typical Performance Curves Ð Contd. Frequency Response for Different Gains, VS e g 5V Input Common-Mode Rejection Ratio vs Frequency Input Voltage and Current Noise vs Frequency 4453 – 11 4453 – 5 4453 – 8 VIN Differential Gain Error vs Input Offset Voltage for Gain e 100%, 75%, 50% and 25% VIN Differential Gain and Phase Error vs Gain 4453 – 14 4453 – 15 VIN Differential Phase Error vs Input Offset Voltage for Gain e 100%, 75%, 50% and 25%. VS e g 5V VIN Differential Phase Error vs Input Offset Voltage for Gain e 100%, 75%, 50% and 25%. VS e g 12V 4453 – 16 4453 – 17 5 EL4453C Video Fader Typical Performance Curves Ð Contd. Nonlinearity vs VIN Signal Span Nonlinearity vs Sum Signal Span 4453 – 13 4453 – 12 Slew Rate vs Supply Voltage Slew Rate vs Die Temperature 4453 – 18 4453 – 19 VINA Gain vs VFADE Frequency Response of Fade Input 4453 – 21 4453 – 20 6 EL4453C Video Fader Typical Performance Curves Ð Contd. Transient Response of Fade Input Constant Signal into VINA Overdrive Recovery Glitch from VFADE, No Input Signal 4453 – 22 4453 – 23 VINA Transient Response for Various Gains Cross-Fade Balance with VINA e VINB e 0 4453 – 25 4453 – 24 Supply Current vs Supply Voltage Supply Current vs Die Temperature 4453 – 26 4453 – 27 7 EL4453C Video Fader Applications Information The EL4453C is a complete two-quadrant fader/ gain control with 80 MHz bandwidth. It has four sets of inputs; a differential signal input VINA, a differential signal input VINB, a differential fade-controlling input VFADE, and another differential input Sum which can be used to add in a third input at full gain. This is the general connection of the EL4453C: 4453 – 28 8 EL4453C Video Fader The EL4453C is stable for a direct connection between VOUT and VINA b or VINB b , yielding a gain of a 1. The feedback divider may be used for higher output gain, although with the traditional loss of bandwidth. It is important to keep the feedback dividers’ impedances low so that stray capacitance does not diminish the feedback loop’s phase margin. The pole caused by the parallel impedance of the feedback resistors and stray capacitance should be at least 150 MHz; typical strays of 3 pF thus require a feedback impedance of 360X or less. Alternatively, a small capacitor across RF can be used to create more of a frequency-compensated divider. The value of the capacitor should scale with the parasitic capacitance at the FB input. It is also practical to place small capacitors across both the feedback resistors (whose values maintain the desired gain) to swamp out parasitics. For instance, two 10 pF capacitors across equal divider resistors for a gain of two will dominate parasitic effects and allow a higher divider resistance. Either input channel can be set up for inverting gain using traditional feedback resistor connections. Applications Information Ð Contd. The gain of the feedback dividers are HA and HB, and 0 s H s 1. The transfer function of the part is VOUT e AO c [((VINA a ) – HA c VOUT) c (1 a (VFADE a ) b (VFADE b ))/2 a ((VINB a ) – HB c VOUT) c (1 b (VFADE a ) a (VFADE b ))/2 a (Sum a ) –(Sum b ))] , with b 1 s (VFADE a ) – (VFADE b ) s a 1 numerically. AO is the open-loop gain of the amplifier, and is about 600. The large value of AO drives ((VINA a ) – HA c VOUT) c (1 a (VFADE a ) – (VFADE b ))/2 a ((VINB a ) – HB c VOUT) c (1 b (VFADE a ) a (VFADE b ))/2 a (Sum a ) – (Sum b )) 0. x Rearranging and substituting VOUT e F c VINA a F c VINB a Sum F c HA a F c HB At 100% gain, an input stage operates just like an op-amp’s input, and the gain error is very low, around b 0.2%. Furthermore, nonlinearities are vastly improved since the gain core sees only small error signals, not full inputs. Unfortunately, distortions increase at lower fade gains for a given input channel. Where F e (1 a (VFADE a ) – (VFADE b ))/2, F e (1 b (VFADE a ) a (VFADE b ))/2, and Sum e (Sum a )–(Sum b ) In the above equations, F represents the fade amount, with F e 1 giving 100% gain on VINA but 0% for VINB; F e 0 giving 0% gain for VINA but 100% to VINB. F is 1 b F, the complement of the fade gain. When F e 1, VOUT e The Sum pins can be used to inject an additional input signal, but it is not as linear as the VIN paths. The gain error is also not as good as the main inputs, being about 1%. Both sum pins should be grounded if they are not to be used. VINA a Sum HA and the amplifier passes VINA and Sum with a gain of 1/HA. Similarly, for F e 0 VOUT e VINB a Sum HB and the gains vary linearly between fade extremes. 9 EL4453C Video Fader Fade-Control Characteristics The Ground Pin The quantity VFADE in the above equations is bounded as b 1 s VFADE s 1, even though the externally applied voltages often exceed this range. Actually, the gain transfer function around b 1V and a 1V is ‘‘soft’’, that is, the gain does not clip abruptly below the 0%-VFADE voltage or above the 100% – VFADE level. An overdrive of 0.3V must be applied to VFADE to obtain truly 0% or 100%. Because the 0% e or 100%VFADE levels cannot be precisely determined, they are extrapolated from two points measured inside the slope of the gain transfer curve. Generally, an applied VFADE range of b 1.5V to a 1.5V will assure the full span of numerical b 1 s VFADE s 1 and 0 s F s 1. The ground pin draws only 6 mA maximum DC current, and may be biased anywhere between (V b ) a 2.5V and (V a ) b 3.5V. The ground pin is connected to the IC’s substrate and frequency compensation components. It serves as a shield within the IC and enhances input stage CMRR and channel-to-channel isolation over frequency, and if connected to a potential other than ground, it must be bypassed. Power Supplies The EL4453C works well on any supplies from g 3V to g 15V. The supplies may be of different voltages as long as the requirements of the GND pin are observed (see the Ground Pin section for a discussion). The supplies should be bypassed close to the device with short leads. 4.7 mF tantalum capacitors are very good, and no smaller bypasses need be placed in parallel. Capacitors as small as 0.01 mF can be used if small load currents flow. The fade control has a small-signal bandwidth equal to the VIN channel bandwidth, and overload recovery resolves in about 20 ns. Input Connections The input transistors can be driven from resistive and capacitive sources, but are capable of oscillation when presented with an inductive input. It takes about 80 nH of series inductance to make the inputs actually oscillate, equivalent to four inches of unshielded wiring or about six inches of unterminated input transmission line. The oscillation has a characteristic frequency of 500 MHz. Often placing one’s finger (via a metal probe) or an oscilloscope probe on the input will kill the oscillation. Normal high frequency construction obviates any such problems, where the input source is reasonably close to the fader input. If this is not possible, one can insert series resistors of around 51X to de-Q the inputs. Singe-polarity supplies, such as a 12V with a 5V can be used, where the ground pin is connected to a 5V and V b to ground. The inputs and outputs will have to have their levels shifted above ground to accommodate the lack of negative supply. The dissipation of the fader increases with power supply voltage, and this must be compatible with the package chosen. This is a close estimate for the dissipation of a circuit: PD e 2 c VS, max c VS a (VS b VO) c VO/RPAR where Signal Amplitudes Signal input common-mode voltage must be between (V b ) a 2.5V and (V a ) b 2.5V to ensure linearity. Additionally, the differential voltage on any input stage must be limited to g 6V to prevent damage. The differential signal range is g 2V in the EL4453C. The input range is substantially constant with temperature. 10 IS, max is the maximum supply current VS is the g supply voltage (assumed equal) VO is the output voltage RPAR is the parallel of all resistors loading the output EL4453C Video Fader This allows g 15V operation over the commercial temperature range, but higher ambient temperature or output loading may require lower supply voltages. Power Supplies Ð Contd. For instance, the EL4453C draws a maximum of % and the 21 mA. With light loading, RPAR dissipation with g 5V supplies is 210 mW. The maximum supply voltage that the device can run on for a given PD and the other parameters is x Output Loading The output stage of the EL4453C is very powerful. It typically can source 80 mA and sink 120 mA. Of course, this is too much current to sustain and the part will eventually be destroyed by excessive dissipation or by metal traces on the die opening. The metal traces are completely reliable while delivering the 30 mA continuous output given in the Absolute Maximum Ratings table in this data sheet, or higher purely transient currents. VS, max e (PD a VO2/RPAR)/(2IS a VO/RPAR) The maximum dissipation a package can offer is PD, max e (TD, max b TA, max)/iJA where TD, max is the maximum die temperature, 150§ C for reliability, less to retain optimum electrical performace TA, max is the ambient temperature, 70§ C for commercial and 85§ C for industrial range iJA is the thermal resistance of the mounted package, obtained from datasheet dissipation curves Gain changes only 0.2% from no load to 100X load. Heavy resistive loading will degrade frequency response and video distortion for loads k 100X. Capacitive loads will cause peaking in the frequency response. If capacitive loads must be driven, a small-valued series resistor can be used to isolate it. 12X to 51X should suffice. A 22X series resistor will limit peaking to 2.5 dB with even a 220 pF load. The more difficult case is the SO-14 package. With a maximum die temperature of 150§ C and a maximum ambient temperature of 70§ C, the 80§ C temperature rise and package thermal resistance of 110§ /W gives a dissipation of 636 mW at 85 § C. 11 EL4453C EL4453C Video Fader 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. January 1995 Rev A 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.