Datasheet AD8451 (Analog Devices) - 9

AD8451 Data Sheet Pin No. Mnemonic Input/Output1 Description
36, 61, 72 AVEE N/A Analog Negative Supply Pins. The default voltage is −15 V. 37 BVMEA Output Voltage Sense Difference Amplifier Output. 38, 57, 70 AVCC N/A Analog Positive Supply Pins. The default voltage is 15 V. 39 MODE Input TTL Compliant Logic Input Selects Charge or Discharge Mode. Low = discharge, high = charge. 45 DGND N/A Digital Ground Pin. 47 DVCC N/A Digital Supply. The default voltage is 5 V. 49 VSET Input Target Voltage for the Voltage Sense Control Loop. 50 VSETBF Output Buffered Voltage VSET. 51 VVP0 Input Noninverting Input of the Voltage Sense Integrator for Discharge Mode. 53 VVE0 Input Inverting Input Voltage for the Voltage Sense Integrator for Discharge Mode. 54 VVE1 Input Inverting Input of the Voltage Sense Integrator for Charge Mode. 56, 62 VINT Output Minimum Output of the Voltage Sense and Current Sense Integrator Amplifiers. 58 VCLN Input Low Clamp Voltage for VCTRL. 59 VCTRL Output Controller Output Voltage. Connect this pin to the input of the PWM controller (for example, the COMP pin of the ADP1972). 60 VCLP Input High Clamp Voltage for VCTRL. 64 IVE1 Input Inverting Input of the Current Sense Integrator for Charge Mode. 65 IVE0 Input Inverting Input of the Current Sense Integrator for Discharge Mode. 67 ISET Input Target Voltage for the Current Sense Control Loop. 68 ISREFB Output Buffered Voltage ISREFL. 71 ISMEA Output Current Sense Instrumentation Amplifier Output. 74 ISREFH Input Reference Input for the Current Sense Amplifier. To level shift the current sense instrumentation amplifier output by approximately 20 mV, connect this pin to the VREF pin. Otherwise, connect this pin to the ISREFL pin. 76 ISREFL Input Reference Input for the Current Sense Amplifier. The default connection is to ground. 77 ISREFLS Input Kelvin Sense Pin for the ISREFL Pin. 1 N/A means not applicable. Rev. 0 | Page 8 of 32 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS IA CHARACTERISTICS DA CHARACTERISTICS CC AND CV LOOP FILTER AMPLIFIERS, AND VSET BUFFER VINT BUFFER REFERENCE CHARACTERISTICS THEORY OF OPERATION OVERVIEW INSTRUMENTATION AMPLIFIER (IA) Reversing Polarity When Charging and Discharging IA Offset Option Battery Reversal and Overvoltage Protection DIFFERENCE AMPLIFIER (DA) CC AND CV LOOP FILTER AMPLIFIERS Compensation VINT Buffer MODE PIN, CHARGE AND DISCHARGE CONTROL APPLICATIONS INFORMATION FUNCTIONAL DESCRIPTION POWER SUPPLY CONNECTIONS CURRENT SENSE IA CONNECTIONS Current Sensors Optional Low-Pass Filter VOLTAGE SENSE DA CONNECTIONS Reverse Battery Conditions BATTERY CURRENT AND VOLTAGE CONTROL INPUTS (ISET AND VSET) LOOP FILTER AMPLIFIERS CONNECTING TO A PWM CONTROLLER (VCTRL PIN) STEP-BY-STEP DESIGN EXAMPLE Step 1: Design the Switching Power Converter Step 2: Identify the Control Voltage Range of the ADP1972 Step 3: Determine the Control Voltage for the CV Loop Step 4: Determine the Control Voltage for the CC Loop and the Shunt Resistor Step 5: Choose the Control Voltage Sources Step 6: Select the Compensation Devices EVALUATION BOARD INTRODUCTION FEATURES AND TESTS EVALUATING THE AD8451 Test the Instrumentation Amplifier 20 mV Offset at IMEAS Output Test the Difference Amplifier 5 mV Offset at BVMEAS Output CC and CV Integrator Tests Loop Compensation SCHEMATIC AND ARTWORK OUTLINE DIMENSIONS ORDERING GUIDE