Datasheet ADP1882, ADP1883 (Analog Devices) - 6

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ADP1882/ADP1883 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS VIN 1 10 BST COMP/EN 2 ADP1882/ 9 SW ADP1883 FB 3 8 DRVH TOP VIEW GND 4 7 PGND (Not to Scale)
03 0
VDD 5 6 DRVL
1- 90 08 Figure 3. Pin Configuration
Table 4. Pin Function Descriptions Pin No. Mnemonic Description
1 VIN High Input Voltage. Connect VIN to the drain of the upper-side MOSFET. 2 COMP/EN Output of the Internal Error Amplifier/IC Enable. When this pin functions as EN, applying 0 V to this pin disables the IC. 3 FB Noninverting Input of the Internal Error Amplifier. This is the node where the feedback resistor is connected. 4 GND Analog Ground Reference Pin of the IC. All sensitive analog components should be connected to this ground plane (see the Layout Considerations section). 5 VDD Bias Voltage Supply for the ADP1882/ADP1883 Controller, Including the Output Gate Drivers. A bypass capacitor of 1 μF directly from this pin to PGND and a 0.1 μF across VDD and GND are recommended. 6 DRVL Drive Output for the External Lower-Side N-Channel MOSFET. This pin also serves as the current-sense gain setting pin (see Figure 69). 7 PGND Power GND. Ground for the lower-side gate driver and lower-side N-channel MOSFET. 8 DRVH Drive Output for the External Upper-Side, N-Channel MOSFET. 9 SW Switch Node Connection. 10 BST Bootstrap for the Upper-Side MOSFET Gate Drive Circuitry. An internal boot rectifier (diode) is connected between VDD and BST. A capacitor from BST to SW is required. An external Schottky diode can also be connected between VDD and BST for increased gate drive capability. Rev. 0 | Page 6 of 40 Document Outline FEATURES APPLICATIONS TYPICAL APPLICATIONS CIRCUIT GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE BOUNDARY CONDITION ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS ADP1882/ADP1883 BLOCK DIAGRAM THEORY OF OPERATION STARTUP SOFT START PRECISION ENABLE CIRCUITRY UNDERVOLTAGE LOCKOUT THERMAL SHUTDOWN PROGRAMMING RESISTOR (RES) DETECT CIRCUIT VALLEY CURRENT-LIMIT SETTING HICCUP MODE DURING SHORT CIRCUIT SYNCHRONOUS RECTIFIER POWER SAVING MODE (PSM) VERSION (ADP1883) TIMER OPERATION PSEUDO-FIXED FREQUENCY APPLICATIONS INFORMATION FEEDBACK RESISTOR DIVIDER INDUCTOR SELECTION OUTPUT RIPPLE VOLTAGE (ΔVRR) OUTPUT CAPACITOR SELECTION COMPENSATION NETWORK Output Filter Impedance (ZFILT) Error Amplifier Output Impedance (ZCOMP) Error Amplifier Gain (GM) Current-Sense Loop Gain (GCS) Crossover Frequency EFFICIENCY CONSIDERATIONS Channel Conduction Loss MOSFET Driver Loss Switching Loss Diode Conduction Loss Inductor Loss INPUT CAPACITOR SELECTION THERMAL CONSIDERATIONS DESIGN EXAMPLE Input Capacitor Inductor Current Limit Programming Output Capacitor Feedback Resistor Network Setup Compensation Network Loss Calculations EXTERNAL COMPONENT RECOMMENDATIONS LAYOUT CONSIDERATIONS IC SECTION (LEFT SIDE OF EVALUATION BOARD) POWER SECTION DIFFERENTIAL SENSING TYPICAL APPLICATIONS CIRCUITS DUAL-INPUT, 300 kHz HIGH CURRENT APPLICATIONS CIRCUIT SINGLE-INPUT, 600 kHz APPLICATIONS CIRCUIT DUAL-INPUT, 300 kHz HIGH CURRENT APPLICATIONS CIRCUIT OUTLINE DIMENSIONS ORDERING GUIDE