Preliminary Technical Data FEATURES Extremely low harmonic distortion −108 dBc HD2 @ 10 MHz −79 dBc HD2 @ 70 MHz −125 dBc HD3 @ 10 MHz −87 dBc HD3 @ 70 MHz Low input voltage noise: 2.2 nV/√Hz High speed −3 dB bandwidth of 1.5 GHz, G = 1 Slew rate: 4700 V/μs 0.1 dB gain flatness to 125 MHz Fast settling to 0.01% in 8.5 ns Fast overdrive recovery of 4 ns 1 mV typical offset voltage Externally adjustable gain Differential to differential or single-ended to differential operation Adjustable output common-mode voltage Wide Supply Voltage Range: +5 V & ± 5 V Pb-free 3 mm x 3 mm LFCSP package Ultra-Low Distortion Differential ADC Driver ADA4938-1 FUNCTIONAL BLOCK DIAGRAM Figure 1. APPLICATIONS ADC drivers Single-ended-to-differential converters IF and baseband gain blocks Differential buffers Line drivers GENERAL DESCRIPTION The ADA4938-1 is a low noise, ultra-low distortion, high speed differential amplifier. It is an ideal choice for driving high performance ADCs with resolutions up to 16 bits from dc to 70 MHz. The output common mode voltage is adjustable over a wide range, allowing the ADA4938-1 to match the input of the ADC. The internal common mode feedback loop also provides exceptional output balance as well as suppression of even-order harmonic distortion products. Full differential and single-ended to differential gain configurations are easily realized with the ADA4938-1. A simple external feedback network of four resistors determines the amplifier’s closed-loop gain. The ADA4938-1 is fabricated using ADI’s proprietary third generation high-voltage XFCB process, enabling it to achieve very low levels of distortion with input voltage noise of only 2.2 nV/√Hz. The low dc offset and excellent dynamic performance of the ADA4938-1 make it well suited for a wide variety of data acquisition and signal processing and applications. The ADA4938-1 is available in a Pb-free, 3 mm x 3mm lead frame chip scale package (LFCSP). It is specified to operate over the extended industrial temperature range of −40°C to +85°C. Rev. PrA Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2006 Analog Devices, Inc. All rights reserved. ADA4938-1 Preliminary Technical Data TABLE OF CONTENTS Features .............................................................................................. 1 Single Supply Operation...............................................................5 Applications....................................................................................... 1 Absolute Maximum Ratings ............................................................7 Functional Block Diagram .............................................................. 1 Thermal Resistance .......................................................................7 General Description ......................................................................... 1 ESD Caution...................................................................................7 Revision History ............................................................................... 2 Pin Configuration and Function Descriptions..............................8 Specifications..................................................................................... 3 Outline Dimensions ..........................................................................9 Dual Supply Operation ................................................................ 3 Ordering Guide .............................................................................9 REVISION HISTORY 12/06—Revision PrA: Initial Version Rev. PrA | Page 2 of 9 Preliminary Technical Data ADA4938-1 SPECIFICATIONS DUAL SUPPLY OPERATION At 25 °C, +VS = 5 V, −VS = −5 V, VOCM = 0 V, RG = RF = 200 Ω, G = +1, RL, dm = 1 kΩ, unless otherwise noted. All specifications refer to single-ended input and differential outputs, unless otherwise noted. Table 1. Parameter ±DIN TO ±OUT PERFORMANCE DYNAMIC PERFORMANCE −3 dB Small Signal Bandwidth Bandwidth for 0.1 dB Flatness Large Signal Bandwidth Slew Rate Settling Time Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE 1 Second Harmonic Third Harmonic IMD IP3 Voltage Noise (RTI) Noise Figure Input Current Noise INPUT CHARACTERISTICS Offset Voltage Conditions Min Input Capacitance Input Common-Mode Voltage CMRR OUTPUT CHARACTERISTICS Output Voltage Swing Output Current Output Balance Error VOCM to ±OUT PERFORMANCE VOCM DYNAMIC PERFORMANCE −3 dB Bandwidth Slew Rate INPUT VOLTAGE NOISE (RTI) VOCM INPUT CHARACTERISTICS Input Voltage Range Input Resistance Input Offset Voltage Input Bias Current VOCM CMRR Gain POWER SUPPLY Max Unit VOUT = 0.5 V p-p, Differential Input VOUT = 2 V p-p, Differential Input VOUT = 2 V p-p, Differential Input VOUT = 4 V p-p, Differential Input VOUT = 2 V p-p 0.01%, VOUT = 2 Vp-p VIN = 5 V to 0 V step, G = +2 1500 125 1300 800 4700 8.5 4 MHz MHz MHz MHz V/μs ns ns VOUT = 2 V p-p, 10 MHz VOUT = 2 V p-p, 70 MHz VOUT = 2 V p-p, 10 MHz VOUT = 2 V p-p, 70 MHz 70 MHz 70 MHz −108 −79 −125 −87 dBc dBc dBc dBc dBc dBm nV/√Hz dB pA/√Hz 2.2 12 2 G = +2 VOS, dm = VOUT, dm/2; VDIN+ = VDIN− = 0 V TMIN to TMAX variation 1 ±4 3.5 −0.01 6 3 1 −4.7 to 3.4 −77 Input Bias Current Input Resistance Typ TMIN to TMAX variation Differential Common mode ∆VOUT, dm/∆VIN, cm; ∆VIN, cm = ±1 V Maximum ∆VOUT; single-ended output 1 ∆VOUT, cm/∆VOUT, dm; ∆VOUT, dm = 1 V; 10 MHz 95 −66 4 V mA dB 400 1700 7.5 MHz V/μs nV/√Hz −3.8 VOS, cm = VOUT, cm; VDIN+ = VDIN– = 0 V ∆VOUT, dm/∆VOCM; ∆VOCM = ±1 V ∆VOUT, cm/∆VOCM; ∆VOCM = ±1 V Rev. PrA | Page 3 of 9 mV μV/°C μA μA/°C MΩ MΩ pF V dB 3.8 200 1 0.5 −75 1 3.5 V kΩ mV μA dB V/V ADA4938-1 Parameter Operating Range Quiescent Current Power Supply Rejection Ratio POWER DOWN (PD) PD Input Voltage Turn-Off Time Turn-On Time PD Bias Current Enabled Disabled Preliminary Technical Data Conditions Min 4.5 40 40 <1 −90 Unit V mA μA/°C mA dB Powered down Enabled ≤1 ≥2 1 200 V V μs ns PD = 5 V PD = 0 V 40 200 μA μA TMIN to TMAX variation Powered down ∆VOUT, dm/∆VS; ∆VS = ±1 V OPERATING TEMPERATURE RANGE −40 Rev. PrA | Page 4 of 9 Typ Max 12 +85 °C Preliminary Technical Data ADA4938-1 SINGLE SUPPLY OPERATION At 25 °C, +VS = 5 V, -VS = 0 V, VOCM = 2.5 V, RG = RF = 200 Ω, G = +1, RL, dm = 1 kΩ, unless otherwise noted. All specifications refer to single-ended input and differential output, unless otherwise noted. Table 2. Parameter ±DIN TO ±OUT PERFORMANCE DYNAMIC PERFORMANCE −3 dB Small Signal Bandwidth Bandwidth for 0.1 dB Flatness Large Signal Bandwidth Slew Rate Settling Time Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE Second Harmonic Third Harmonic IMD IP3 Voltage Noise (RTI) Noise Figure Input Current Noise INPUT CHARACTERISTICS Offset Voltage Conditions Min Input Capacitance Input Common-Mode Voltage CMRR OUTPUT CHARACTERISTICS Output Voltage Swing Output Current Output Balance Error VOCM TO ±OUT PERFORMANCE VOCM DYNAMIC PERFORMANCE −3 dB Bandwidth Slew Rate INPUT VOLTAGE NOISE (RTI) VOCM INPUT CHARACTERISTICS Input Voltage Range Input Resistance Input Offset Voltage Input Bias Current VOCM CMRR Gain POWER SUPPLY Operating Range Quiescent Current Max Unit VOUT = 0.5 V p-p, Differential Input VOUT = 2 V p-p, Differential Input VOUT = 2 V p-p, Differential Input VOUT = 2 V p-p 0.01%, VOUT = 2 V p-p VIN = 2.5 V to 0 V step, G = +2 1500 125 1100 3900 8.1 4 MHz MHz MHz V/μs ns ns VOUT = 2 V p-p, 10 MHz VOUT = 2 V p-p, 70 MHz VOUT = 2 V p-p, 10 MHz VOUT = 2 V p-p, 70 MHz 70 MHz 70 MHz −115 −87 −110 −79 dBc dBc dBc dBc dBc dBm nV/√Hz dB pA/√Hz 2.2 12 2 G = +2 VOS, dm = VOUT, dm/2; VDIN+ = VDIN− = VOCM = 2.5 V TMIN to TMAX variation 1 ±4 3.5 −0.01 6 3 1 0.3 to 3.4 −77 Input Bias Current Input Resistance Typ TMIN to TMAX variation Differential Common mode ∆VOUT, dm/∆VIN, cm; ∆VIN, cm = ±1 V Maximum ∆VOUT; single-ended output 1.1 3.9 ∆VOUT, cm/∆VOUT, dm; ∆VOUT, dm = 1 V 95 −66 V = 0.5 V 400 1700 1.2 ∆VOUT, dm/∆VOCM; ∆VOCM = ±1 V ∆VOUT, cm/∆VOCM; ∆VOCM = ±1 V 4.5 Rev. PrA | Page 5 of 9 36 40 V mA dB MHz V/μs nV/√Hz 3.8 V kΩ mV μA dB V/V 12 V mA μA/°C 200 1 0.5 −75 1 VOS, cm = VOUT, cm; VDIN+ = VDIN– = VOCM = 2.5 V TMIN to TMAX variation mV μV/°C μA μA/°C MΩ MΩ pF V dB ADA4938-1 Parameter Power Supply Rejection Ratio POWER DOWN (PD) PD Input Voltage Turn-Off Time Turn-On Time PD Bias Current Enabled Disabled Preliminary Technical Data Conditions Powered down ∆VOUT, dm/∆VS; ∆VS = ±1 V Min Powered down Enabled PD = 5 V PD = 0 V OPERATING TEMPERATURE RANGE −40 Rev. PrA | Page 6 of 9 Typ <1 −90 Max Unit mA dB ≤1 ≥2 1 200 V V μs ns 20 −120 μA μA +85 °C Preliminary Technical Data ADA4938-1 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Supply Voltage Power Dissipation Storage Temperature Range Operating Temperature Range Lead Temperature (Soldering, 10 sec) Junction Temperature Rating TBD See Figure 2 −65°C to +125°C −40°C to +85°C 300°C 150°C Stresses above those listed under Absolute Maximum Rating may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. The power dissipated in the package (PD) is the sum of the quiescent power dissipation and the power dissipated in the package due to the load drive. The quiescent power is the voltage between the supply pins (VS) times the quiescent current (IS). The power dissipated due to the load drive depends upon the particular application. The power due to load drive is calculated by multiplying the load current by the associated voltage drop across the device. RMS voltages and currents must be used in these calculations. Airflow increases heat dissipation, effectively reducing θJA. In addition, more metal directly in contact with the package leads/exposed pad from metal traces, through-holes, ground, and power planes reduces the θJA. Figure 2 shows the maximum safe power dissipation in the package vs. the ambient temperature for the 16-lead LFCSP (TBD °C/W) on a JEDEC standard 4-layer board. THERMAL RESISTANCE θJA is specified for the worst-case conditions; that is, θJA is specified for a device (including exposed pad) soldered to the circuit board. Table 4. Thermal Resistance Package Type 16-Lead LFCSP (Exposed Pad) θJA TBD Unit °C/W Maximum Power Dissipation The maximum safe power dissipation in the ADA4938-1 package is limited by the associated rise in junction temperature (TJ) on the die. At approximately 150°C, which is the glass transition temperature, the plastic changes its properties. Even temporarily exceeding this temperature limit can change the stresses that the package exerts on the die, permanently shifting the parametric performance of the ADA4938-1. Exceeding a junction temperature of 150°C for an extended period can result in changes in the silicon devices, potentially causing failure. Figure 2. Maximum Power Dissipation vs. Temperature for a 4-Layer Board ESD CAUTION Rev. PrA | Page 7 of 9 ADA4938-1 Preliminary Technical Data PIN CONFIGURATION AND FUNCTION DESCRIPTIONS FB-OUT 1 PIN 1 INDICATOR -IN 3 FB+OUT 4 12 PD 11 -OUT +IN 2 TOP VIEW 10 +OUT 9 VOCM Figure 3. Pin Configuration Table 5. Pin Function Descriptions Pin No. 1 2 3 4 5 to 8 9 10 11 12 13 to 16 Mnemonic FB-OUT +IN −IN FB+OUT +VS VOCM +OUT −OUT PD −VS Description Negative output feedback pin Positive input summing node Negative input summing node Positive output feedback pin Positive supply voltage Output common mode voltage Positive output Negative output Power-down pin Negative supply voltage B B Rev. PrA | Page 8 of 9 Preliminary Technical Data ADA4938-1 OUTLINE DIMENSIONS 3.00 BSC SQ 0.60 MAX 13 12 0.45 PIN 1 INDICATOR TOP VIEW 2.75 BSC SQ 0.80 MAX 0.65 TYP 12° MAX 0.90 0.85 0.80 16 PIN 1 INDICATOR *1.65 1 1.50 SQ 1.35 EXPOSED PAD 0.50 BSC SEATING PLANE 0.50 0.40 0.30 9 (BOTTOM VIEW) 4 8 5 0.25 MIN 1.50 REF 0.05 MAX 0.02 NOM 0.30 0.23 0.18 0.20 REF *COMPLIANT TO JEDEC STANDARDS MO-220-VEED-2 EXCEPT FOR EXPOSED PAD DIMENSION. Figure 4. 16-Lead Lead Frame Chip Scale Package [LFCSP_VQ] 3 mm × 3 mm Body (CP-16-3) Dimensions shown in millimeters ORDERING GUIDE Model ADA4938-1YCPZ-R2 ADA4938-1YCPZ-RL ADA4938-1YCPZ-R7 Ordering Quantity 5,000 1,500 250 Temperature Range −40°C to +85°C −40°C to +85°C −40°C to +85°C Package Description 16-Lead 3 mm × 3 mm LFCSP 16-Lead 3 mm × 3 mm LFCSP 16-Lead 3 mm × 3 mm LFCSP Package Option CP-16 -3 CP-16 -3 CP-16 -3 Branding ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. PR06592-0-12/06(PrA) T T Rev. PrA | Page 9 of 9