INTEGRATED CIRCUITS SA5219 Wideband variable gain amplifier Product specification Replaces data of 1993 Dec 10 IC17 Data Handbook Philips Semiconductors 1997 Nov 07 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 DESCRIPTION PIN CONFIGURATION The SA5219 represents a breakthrough in monolithic amplifier design featuring several innovations. This unique design has combined the advantages of a high speed bipolar process with the proven Gilbert architecture. N, D PACKAGES VCC1 1 16 VCC2 The SA5219 is a linear broadband RF amplifier whose gain is controlled by a single DC voltage. The amplifier runs off a single 5 volt supply and consumes only 40mA. The amplifier has high impedance (1kΩ) differential inputs. The output is 50Ω differential. Therefore, the 5219 can simultaneously perform AGC, impedance transformation, and the balun functions. GND1 2 15 GND2 INA 3 14 OUTA GND1 4 13 GND2 INB 5 12 OUTB GND1 6 11 GND2 The dynamic range is excellent over a wide range of gain setting. Furthermore, the noise performance degrades at a comparatively slow rate as the gain is reduced. This is an important feature when building linear AGC systems. VBG 7 10 GND2 VAGC 8 9 GND2 SR00273 Figure 1. Pin Configuration FEATURES • 700MHz bandwidth • High impedance differential input • 50Ω differential output • Single 5V power supply • 0 - 1V gain control pin • >60dB gain control range at 200MHz • 26dB maximum gain differential • Exceptional VCONTROL / VGAIN linearity • 7dB noise figure minimum • Full ESD protection • Easily cascadable APPLICATIONS • Linear AGC systems • Very linear AM modulator • RF balun • Cable TV multi-purpose amplifier • Fiber optic AGC • RADAR • User programmable fixed gain block • Video • Satellite receivers • Cellular communications ORDERING INFORMATION Temperature Range Order Code DWG # 16-Pin Plastic Small Outline (SO) package Description -40 to +85°C SA5219D SOT109-1 16-Pin Plastic Dual In-Line package (DIP) -40 to +85°C SA5219N SOT38-4 1997 Nov 07 2 853-1724 18663 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 ABSOLUTE MAXIMUM RATINGS SYMBOL PARAMETER RATING UNITS VCC Supply voltage -0.5 to +8.0 V PD Power dissipation, TA = 25oC (still air)1 16-Pin Plastic DIP 16-Pin Plastic SO 1450 1100 mW mW TJMAX Maximum operating junction temperature 150 °C TSTG Storage temperature range -65 to +150 °C NOTES: 1. Maximum dissipation is determined by the operating ambient temperature and the thermal resistance, θJA: 16-Pin DIP: θJA = 85°C/W 16-Pin SO: θJA = 110°C/W RECOMMENDED OPERATING CONDITIONS SYMBOL VCC PARAMETER Supply voltage RATING UNITS VCC1 = VCC2 = 4.5 to 7.0V V TA Operating ambient temperature range SA Grade -40 to +85 °C TJ Operating junction temperature range SA Grade -40 to +105 °C DC ELECTRICAL CHARACTERISTICS TA = 25oC, VCC1 = VCC2 = +5V, VAGC = 1.0V, unless otherwise specified. LIMITS SYMBOL PARAMETER TEST CONDITIONS MIN TYP MAX UNIT ICC Supply current DC tested 36 43 50 mA AV Voltage gain (single-ended in/single-ended out) DC tested, RL = 10kΩ 16 19 22 dB AV Voltage gain (single-ended in/differential out) DC tested, RL = 10kΩ 22 25 28 dB RIN Input resistance (single-ended) DC tested at ±50µA 0.8 1.2 1.6 kΩ ROUT Output resistance (single-ended) DC tested at ±1mA 35 60 80 Ω VOS Output offset voltage (output referred) +20 ±150 mV VIN DC level on inputs 1.6 2.0 2.4 V VOUT DC level on outputs 1.9 2.4 2.9 V PSRR Output offset supply rejection ratio 18 45 1.2 1.32 2 10 kΩ 0-1.3 V VBG Bandgap reference voltage RBG Bandgap loading VAGC AGC DC control voltage range IBAGC AGC pin DC bias current 1997 Nov 07 4.5V<VCC<7V RBG = 10kΩ 0V<VAGC<1.3V 3 -0.7 dB 1.45 -6 V µA Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 AC ELECTRICAL CHARACTERISTICS TA = 25oC, VCC1 = VCC2 = +5.0V, VAGC = 1.0V, unless otherwise specified. LIMITS SYMBOL PARAMETER BW -3dB bandwidth GF Gain flatness VIMAX VOMAX NF VIN-EQ S12 ∆G/∆VCC ∆G/∆T CIN TEST CONDITIONS DC - 500MHz Maximum input voltage swing (single-ended) for linear operation1 MIN TYP MAX UNIT 700 MHz +0.4 dB 200 mVP-P Maximum output voltage swing (single-ended) RL = 50Ω 400 mVP-P for linear operation1 RL = 1kΩ 1.9 VP-P RS = 50Ω, f = 50MHz 9.3 dB Equivalent input noise voltage spectral density f = 100MHz 2.5 nV/√Hz Reverse isolation f = 100MHz -60 dB 0.3 dB/V 0.013 dB/°C 2 pF Noise figure (unmatched configuration) Gain supply sensitivity (single-ended) Gain temperature sensitivity RL = 50Ω Input capacitance (single-ended) BWAGC -3dB bandwidth of gain control function PO-1dB 1dB gain compression point at output 20 MHz f = 100MHz -3 dBm PI-1dB 1dB gain compression point at input f = 100MHz, VAGC =0.1V -10 dBm IP3OUT Third-order intercept point at output f = 100MHz, VAGC >0.5V +13 dBm IP3IN Third-order intercept point at input f = 100MHz, VAGC <0.5V +5 dBm ∆GAB Gain match output A to output B f = 100MHz, VAGC = 1V 0.1 dB NOTE: 1. With RL > 1kΩ, overload occurs at input for single-ended gain < 13dB and at output for single-ended gain > 13dB. With RL = 50Ω, overload occurs at input for single-ended gain < 6dB and at output for single-ended gain > 6dB. Otherwise, there is an advantage to common mode rejection, a specification that is not normally important to RF designs. The source impedance can be chosen for two different performance characteristics: Gain, or noise performance. Gain optimization will be realized if the input impedance is matched to about 1kΩ. A 4:1 balun will provide such a broadband match from a 50Ω source. Noise performance will be optimized if the input impedance is matched to about 200Ω. A 2:1 balun will provide such a broadband match from a 50Ω source. The minimum noise figure can then be expected to be about 7dB. Maximum gain will be about 23dB for a single-ended output. If the differential output is used and properly matched, nearly 30dB can be realized. With gain optimization, the noise figure will degrade to about 8dB. With no matching unit at the input, a 9dB noise figure can be expected from a 50Ω source. If the source is terminated, the noise figure will increase to about 15dB. All these noise figures will occur at maximum gain. SA5219 APPLICATIONS The SA5219 is a wideband variable gain amplifier (VGA) circuit which finds many applications in the RF, IF and video signal processing areas. This application note describes the operation of the circuit and several applications of the VGA. The simplified equivalent schematic of the VGA is shown in Figure 2. Transistors Q1-Q6 form the wideband Gilbert multiplier input stage which is biased by current source I1. The top differential pairs are biased from a buffered and level-shifted signal derived from the VAGC input and the RF input appears at the lower differential pair. The circuit topology and layout offer low input noise and wide bandwidth. The second stage is a differential transimpedance stage with current feedback which maintains the wide bandwidth of the input stage. The output stage is a pair of emitter followers with 50Ω output impedance. There is also an on-chip bandgap reference with buffered output at 1.3V, which can be used to derive the gain control voltage. The SA5219 has an excellent noise figure vs gain relationship. With any VGA circuit, the noise performance will degrade with decreasing gain. The 5219 has about a 1.2dB noise figure degradation for each 2dB gain reduction. With the input matched for optimum gain, the 8dB noise figure at 23dB gain will degrade to about a 20dB noise figure at 0dB gain. Both the inputs and outputs should be capacitor coupled or DC isolated from the signal sources and loads. Furthermore, the two inputs should be DC isolated from each other and the two outputs should likewise be DC isolated from each other. The SA5219 was designed to provide optimum performance from a 5V power source. However, there is some range around this value (4.5 - 7V) that can be used. The SA5219 also displays excellent linearity between voltage gain and control voltage. Indeed, the relationship is of sufficient linearity that high fidelity AM modulation is possible using the SA5219. A The input impedance is about 1kΩ. The main advantage to a differential input configuration is to provide the balun function. 1997 Nov 07 4 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 BAT17 as shown. The diodes are biased by R1 and R2 to VCC such that a quiescent current of about 2mA in each leg is achieved. An SA5230 low voltage op amp is used as an integrator which drives the VAGC pin on all three SA5219s. R3 and C3 filter the high frequency ripple from the full-wave rectified signal. A voltage divider is used to generate the reference for the non-inverting input of the op amp at about 1.7V. Keeping D3 the same type as D1 and D2 will provide a first order compensation for the change in Schottky voltage over the operating temperature range and improve the AGC performance. R6 is a variable resistor for adjustments to the op amp reference voltage. In low cost and large volume applications this could be replaced with a fixed resistor, which would result in a slight loss of the AGC dynamic range. Cascading three SA5219s will give a dynamic range in excess of 60dB. maximum control voltage frequency of about 20MHz permits video baseband sources for AM. A stabilized bandgap reference voltage is made available on the SA5219 (Pin 7). For fixed gain applications this voltage can be resistor divided, and then fed to the gain control terminal (Pin 8). Using the bandgap voltage reference for gain control produces very stable gain characteristics over wide temperature ranges. The gain setting resistors are not part of the RF signal path, and thus stray capacitance here is not important. The wide bandwidth and excellent gain control linearity make the SA5219 VGA ideally suited for the automatic gain control (AGC) function in RF and IF processing in cellular radio base stations, Direct Broadcast Satellite (DBS) decoders, cable TV systems, fiber optic receivers for wideband data and video, and other radio communication applications. A typical AGC configuration using the SA5219 is shown in Figure 3. Three SA5219s are cascaded with appropriate AC coupling capacitors. The output of the final stage drives the full-wave rectifier composed of two UHF Schottky diodes The SA5219 is a very user-friendly part and will not oscillate in most applications. However, in an application such as with gains in excess of 60dB and bandwidth beyond 100MHz, good PC board layout with proper supply decoupling is strongly recommended. VCC R3 R1 R2 Q7 A1 Q8 Q1 Q2 Q3 Q4 OUTB 50Ω R4 I3 I2 VAGC 0–1V OUTA 50Ω + – Q5 INB Q6 BANDGAP REFERENCE INA VBG I1 SR00274 Figure 2. Equivalent Schematic of VGA RF/IF INPUT 5219 AGC OUTPUT 5219 5219 VCC R1 R4 L1 R2 L2 D1 C4 – 5230 + D2 BAT 17 R3 C3 D3 R6 VCC R5 BAT 17 SR00275 Figure 3. AGC Configuration Using Cascaded SA5219s 1997 Nov 07 5 Philips Semiconductors Product specification Wideband variable gain amplifier 10µF SA5219 0.1µF 0.1µF + V VIN 50Ω 1 VCC1 VCC2 16 2 GND1 GND2 15 3 INA OUTA 14 VCC 5VDC OUTA 0.1µF 0.1µF 0.1µF 4 GND1 GND2 13 5 INB OUTB 12 OUTB 0.1µF 6 GND1 GND2 11 7 VBG GND2 10 8 VAGC GND2 9 SR00276 Figure 4. VGA AC Evaluation Board +5V MINI CIRCUITS 2:1 BALUN OR SIMILAR 50Ω 50Ω SOURCE OUTPUT 5219 50Ω 1:2 This circuit will exhibit about a 7dB noise figure with approximately 22dB gain. SR00277 VAGC +1V Figure 5. Broadband Noise Optimization +5V 2:1 TURNS RATIO LC TUNED TRANSFORMER 50Ω OUTPUT 50Ω This circuit will exhibit about a 7dB noise figure with approximately 22dB gain. Narrowband circuits have the advantage of greater stability, particularly when multiple devices are cascaded. 5219 SOURCE 50Ω +1V VAGC SR00278 Figure 6. Narrowband Noise Optimization +5V 50Ω MINI CIRCUITS 4:1 BALUN OR EQUIVALENT 50Ω SOURCE OUTPUT This circuit will exhibit about an 8dB noise figure with 24dB gain. 5219 1:4 50Ω VAGC +1V Figure 7. Broadband Gain Optimization 1997 Nov 07 6 SR00279 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 +5V 4:1 TURNS RATIO LC TUNED TRANSFORMER 50Ω OUTPUT 50Ω This circuit will exhibit approximately an 8dB noise figure and 25dB gain. 5219 SOURCE 50Ω VAGC +1V SR00280 Figure 8. Narrowband Gain Optimization +5V 50Ω 50Ω SOURCE OUTPUT 50Ω The noise figure of this configuration will be approximately 15dB. 5219 50Ω VAGC +1V SR00281 Figure 9. Simple Amplifier Configuration +5V 50Ω 50Ω SOURCE OUTPUT With the 50Ω source left unterminated, the noise figure is 9dB. 5219 50Ω VAGC +1V SR00282 Figure 10. Unterminated Configuration +5V 50Ω 50Ω SOURCE OUTPUT 5219 Gain = 19dB + 20log10 VAGC 50Ω VAGC where VAGC = VBG R1 R2 Figure 11. User-Programmable Fixed Gain Block 1997 Nov 07 7 R2 V R 1 R 2 BG and is in units of Volts, for VAGC ≤ 1V SR00283 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 +5V FULL CARRIER AM (DSB) 50Ω RF INPUT 50Ω OUTPUT 5219 SOURCE 50Ω All harmonic distortion products will be at least -50dBc over the audio spectrum. VAGC .5V R 9R +5V MODULATING SIGNAL SR00284 Figure 12. AM Modulator 50Ω CRYSTAL FILTER OUTPUT 5219 5219 5219 50Ω VAGC VAGC VAGC The high input impedance to the NE5219 makes matching to crystal filters relatively easy. The total delta gain of this system will approach 80dB. IF frequencies well into the UHF region can be configured with this type of architecture. GAIN CONTROL SIGNAL SR00285 Figure 13. Receiver AGC IF Gain VCC (+5V, unless otherwise noted) RS VS ± RT RL 5219 ± RT VAGC RL SR00286 Figure 14. Test Set-up 1 (Used for all Graphs) 1997 Nov 07 8 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 10 20 VCC = 5.5V VCC = 5.0V VCC = 4.5V 9 5.5V 19 Differential Voltage Gain (dB) 8 19.5 S21 Magnitude 7 6 5 T = 25°C RS = RL = 50Ω Rt = ∞ f = 10MHz 4 3 2 5.0V 4.5V 18.5 18 17.5 RS = 0Ω RL = ∞ Rt = ∞ VAGC = 1.1V 17 16.5 See Test Setup 1 16 DC Tested See test-setup 1 1 15.5 0 15 0 0.2 0.4 0.6 0.8 VAGC (V) 1.2 1 –100 –50 0 50 Temperature (°C) 100 150 SR00287 SR00289 Figure 15. Gain vs VAGC and VCC Figure 17. Voltage Gain vs Temperature and VCC -55°C 10 55 +25°C 9 50 8 +125°C 7 Supply Current (mA) 6 S 21 Magnitude VCC = 7.0V 45 5 4 RS = RL = 50Ω Rt = ∞ See test-setup 1 3 2 VCC = 6.0V 40 VCC = 5.0V VCC = 4.5V 35 30 25 See test-setup 1 1 20 0 –100 0 0.2 0.4 0.6 VAGC (V) 0.8 1 1.2 0 50 100 150 Temperature (°C) SR00288 SR00290 Figure 16. Insertion Gain vs VAGC and Temperature 1997 Nov 07 –50 Figure 18. Supply Current vs Temperature and VCC 9 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 1.5 5 1.45 4.5 1.4 4 VCC = 7.0V VCC = 7.0V 3.5 1.3 VCC = 4.5V 3 Output DC Voltage Input Resistance (k Ω ) VCC = 6.0V 1.35 1.25 1.2 1.15 VCC = 5.0V 2.5 VCC = 4.5V 2 1.5 DC Tested See test-setup 1 1 1.1 DC Tested See test-setup 1 1.05 0.5 0 1 –100 –50 0 50 Temperature (°C) 100 –100 150 –50 0 50 100 150 Temperature (°C) SR00291 SR00293 Figure 19. Input Resistance vs Temperature Figure 21. Output Bias Voltage vs Temperature and VCC 2.5 2.5 2 VCC = 7.0V VCC = 6.0V VCC = 5.0V VCC = 4.5V 1.5 DC OUTPUT SWING (V) Input Bias Voltage (V) 2 1 1.5 VAGC = 1.1V RL = 10kΩ DC Tested See test-setup 1 1 0.5 0.5 DC Tested See test-setup 1 0 0 –100 –50 0 50 Temperature (°C) 100 –100 150 0 50 100 150 Temperature (°C) SR00292 SR00294 Figure 20. Input Bias Voltage vs Temperature 1997 Nov 07 –50 Figure 22. DC Output Swing vs Temperature 10 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 16 20 1.1V 14 0.8V 0 0.4V 12 200mV 10 S21 Magnitude (dB) S21 Magnitude (dB) 10 100mV 50mV –10 25mV VCC = 7.0V VCC = 6.0V VCC = 5.0V VCC = 4.5V 8 T = 25°C VAGC = 1.1V Rt = 50Ω f = 10MHz See Test Setup 1 6 4 T = 25°C RS = RL = 50Ω Rt = 50Ω See Test Setup 1 1000 1500 –20 –30 10 100 2 0 –100 –50 50 0 100 150 Temperature (°C) Frequency (MHz) SR00295 SR00297 Figure 23. Insertion Gain vs Frequency and VAGC Figure 25. Insertion Gain vs Temperature and VCC 15 0 5.5V 4.5V –5 S22 (dB) S21 Magnitude (dB) 10 5 –10 125°C –15 T = 25°C VAGC = 1.1V RS = RL = 50Ω Rt = 50Ω See Test Setup 1 0 25°C -55°C –20 RS = RL = 50Ω Rt = 50Ω See Test Setup 1 –5 –25 10 100 10 1000 1500 Frequency (MHz) 1000 1500 SR00298 SR00296 Figure 24. Insertion Gain vs Frequency and VCC 1997 Nov 07 100 Frequency (MHz) Figure 26. Output Return Loss vs Frequency 11 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 0 15 OUTPUT –10 –20 T = 25°C RS = RL = 50Ω Rt = 50Ω f = 100MHz See test-setup 1 –30 IM 3 Intercept (dBm) S Magnitude (dB) 12 10 –40 –50 –60 T = 25°C RS = RL = 50Ω Rt = 50Ω See test-setup 1 –70 5 INPUT 0 –80 Frequency (MHz) –5 1500 10 100 1000 –90 0 0.2 0.4 0.6 0.8 1 VAGC (V) SR00299 SR00301 Figure 27. Reverse Isolation vs Frequency Figure 29. Third-Order Intermodulation Intercept vs VAGC 20 0 OUTPUT 18 –5 16 14 –10 –15 NF (dB) P (dBm) –1 12 INPUT T = 25°C RS = RL = 50Ω Rt = 50Ω f = 100MHz See test-setup 1 –20 10 8 T = 25°C RS = RL = 50Ω Rt = ∞ f = 50MHz See test-setup 1 6 4 –25 2 0 –30 0 0.2 0.4 0.6 0.8 1 0 VAGC (V) 0.2 0.4 0.6 VAGC (V) 0.8 SR00300 SR00302 Figure 28. 1dB Gain Compression vs VAGC 1997 Nov 07 1 Figure 30. Noise Figure vs VAGC 12 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 12 16 14 10 12 S21 Magnitude (dB) 0Ω Termination on INB NF (dB) 10 50Ω Termination on INB 8 6 T = 25°C VAGC = 1.1V RS = RL = 50Ω Rt = ∞ on INA See test-setup 1 4 2 8 6 4 RS = RL = 50Ω Rt = 50Ω R1 = R2 = 10k f = 100MHz See Figure 10 2 0 10 100 Frequency (MHz) 0 1000 –60 –10 40 Temperature (°C) 90 SR00303 SR00305 Figure 31. Noise Figure vs Frequency Figure 33. Fixed Gain vs Temperature 1.4 VCC = 7.0V VCC = 6.0V VCC = 5.0V VCC = 4.5V 1.35 Bandgap Voltage (V) 1.3 1.25 1.2 1.15 1.1 Bandgap Load = 2kΩ 1.05 1 –100 –50 50 0 Temperature (°C) 100 150 SR00304 Figure 32. Bandgap Voltage vs Temperature and VCC 1997 Nov 07 140 13 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 +VCC GND INB OUTA GND AGC VBG INA NE5219 OUTB TOP VIEW - COMPONENT SIDE TOP VIEW - SOLDER SIDE SR00306 Figure 34. VGA AC Evaluation Board Layout (DIP Package) AMP10101 / NE5219SO/DN8.90 TOP VIEW - D Package BOTTOM VIEW - D Package SR00307 Figure 35. VGA AC Evaluation Board Layout (SO Package) 1997 Nov 07 14 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 DIP16: plastic dual in-line package; 16 leads (300 mil) 1997 Nov 07 15 SOT38-4 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 SO16: plastic small outline package; 16 leads; body width 3.9 mm 1997 Nov 07 16 SOT109-1 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 NOTES 1997 Nov 07 17 Philips Semiconductors Product specification Wideband variable gain amplifier SA5219 DEFINITIONS Data Sheet Identification Product Status Definition Objective Specification Formative or in Design This data sheet contains the design target or goal specifications for product development. Specifications may change in any manner without notice. Preliminary Specification Preproduction Product This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips Semiconductors reserves the right to make changes at any time without notice in order to improve design and supply the best possible product. Product Specification Full Production This data sheet contains Final Specifications. Philips Semiconductors reserves the right to make changes at any time without notice, in order to improve design and supply the best possible product. Philips Semiconductors and Philips Electronics North America Corporation reserve the right to make changes, without notice, in the products, including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. LIFE SUPPORT APPLICATIONS Philips Semiconductors and Philips Electronics North America Corporation Products are not designed for use in life support appliances, devices, or systems where malfunction of a Philips Semiconductors and Philips Electronics North America Corporation Product can reasonably be expected to result in a personal injury. Philips Semiconductors and Philips Electronics North America Corporation customers using or selling Philips Semiconductors and Philips Electronics North America Corporation Products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors and Philips Electronics North America Corporation for any damages resulting from such improper use or sale. Copyright Philips Electronics North America Corporation 1997 All rights reserved. Printed in U.S.A. Philips Semiconductors 811 East Arques Avenue P.O. Box 3409 Sunnyvale, California 94088–3409 Telephone 800-234-7381 1997 Nov 07 18