Datasheet AD8331, AD8332, AD8334 (Analog Devices) - 8

AD8331/AD8332/AD8334 Data Sheet PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS LMD 1 20 COMM PIN 1 INH 2 INDICATOR 19 ENBL VPSL 3 18 ENBV LON 4 17 COMM AD8331 LOP 5 16 VOL TOP VIEW COML 6 15 VOH (Not to Scale) VIP 7 14 VPOS VIN 8 13 HILO MODE 9 12 RCLMP
003
GAIN 10 11 VCM
03199- Figure 3. 20-Lead QSOP Pin Configuration (AD8331)
Table 3. 20-Lead QSOP Pin Function Description (AD8331) Pin No. Mnemonic Description
1 LMD LNA Midsupply Bypass Pin; Connect a Capacitor for Midsupply HF Bypass 2 INH LNA Input 3 VPSL LNA 5 V Supply 4 LON LNA Inverting Output 5 LOP LNA Noninverting Output 6 COML LNA Ground 7 VIP VGA Noninverting Input 8 VIN VGA Inverting Input 9 MODE Gain Slope Logic Input 10 GAIN Gain Control Voltage 11 VCM Common-Mode Voltage 12 RCLMP Output Clamping Level 13 HILO Gain Range Select (HI or LO) 14 VPOS VGA 5 V Supply 15 VOH Noninverting VGA Output 16 VOL Inverting VGA Output 17 COMM VGA Ground 18 ENBV VGA Enable 19 ENBL LNA Enable 20 COMM VGA Ground Rev. I | Page 8 of 55 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS TEST CIRCUITS MEASUREMENT CONSIDERATIONS THEORY OF OPERATION OVERVIEW LOW NOISE AMPLIFIER (LNA) Active Impedance Matching LNA Noise VARIABLE GAIN AMPLIFIER X-AMP VGA Gain Control VGA Noise Common-Mode Biasing POSTAMPLIFIER Noise Output Clamping APPLICATIONS INFORMATION LNA—EXTERNAL COMPONENTS Gain Input VCM Input Logic Inputs—ENB, MODE, and HILO Optional Output Voltage Limiting Output Decoupling DRIVING ADCs OVERLOAD OPTIONAL INPUT OVERLOAD PROTECTION LAYOUT, GROUNDING, AND BYPASSING MULTIPLE INPUT MATCHING DISABLING THE LNA ULTRASOUND TGC APPLICATION HIGH DENSITY QUAD LAYOUT AD8331 EVALUATION BOARD GENERAL DESCRIPTION USER-SUPPLIED OPTIONAL COMPONENTS MEASUREMENT SETUP BOARD LAYOUT AD8331 EVALUATION BOARD SCHEMATICS AD8331 EVALUATION BOARD PCB LAYERS AD8332 EVALUATION BOARD GENERAL DESCRIPTION USER-SUPPLIED OPTIONAL COMPONENTS MEASUREMENT SETUP BOARD LAYOUT EVALUATION BOARD SCHEMATICS AD8332 EVALUATION BOARD PCB LAYERS AD8334 EVALUATION BOARD GENERAL DESCRIPTION CONFIGURING THE INPUT IMPEDANCE Driving the VGA from an External Source or Using the LNA to Drive an External Load Using the Clamp Circuit Viewing Signals MEASUREMENT SETUP BOARD LAYOUT EVALUATION BOARD SCHEMATICS AD8334 EVALUATION BOARD PCB LAYERS OUTLINE DIMENSIONS ORDERING GUIDE