link to page 1 link to page 1 link to page 31 link to page 31 link to page 32 ADP1828Data SheetTYPICAL PERFORMANCE CHARACTERISTICS9590300kHz90600kHz8085VIN = 12VfSW = 600kHzV80V%)OUT = 1.8V70IN = 12V(T%)A = 25°C(VOUT = 3.3V75TNCYNCYA = 25°CE 60EICI70ICIFFFFEE5065604055305002468101214161820 002 012345 007 LOAD (A) 06865- LOAD (A) 06865- Figure 5. Efficiency vs. Load Current of Figure 1 Figure 8. Efficiency vs. Load Current of Figure 55 959590908585VIN = 3.3VVVIN = 5.5V80IN = 12VfSW = 300kHz%) 80%)V(( 75IN = 12VVfVIN = 15VSW = 300kHzOUT = 1.8VNCY 75NCYTEVOUT = 1.8V70EA = 25°CICITA = 25°CICIFF 65F 70FEE60655560505545 008 0510152025 005 051015202530LOAD (A)LOAD (A) 06865- 06865- Figure 6. Efficiency vs. Load Current of Figure 1 Figure 9. Efficiency vs. Load Current of Figure 57 955.5T90A = 25°C5.085fSW = 600kHz%) 80(VIN = 3.3V(V) T 4.5VOUT = 1.2VNCYPU75ETA = 25°CT UICI FOF 704.0EEG VR653.56055012345 006 3.0 009 3.03.54.04.55.05.5LOAD (A) 06865- VIN (V) 06865- Figure 7. Efficiency vs. Load Current of Figure 54 Figure 10. VREG in Dropout, No Load Rev. E | Page 10 of 33 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION SIMPLIFIED BLOCK DIAGRAM PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION INPUT POWER INTERNAL LINEAR REGULATOR SOFT START ERROR AMPLIFIER CURRENT-LIMIT SCHEME MOSFET DRIVERS SETTING THE OUTPUT VOLTAGE SWITCHING FREQUENCY CONTROL AND SYNCHRONIZATION COMPENSATION POWER-GOOD INDICATOR THERMAL SHUTDOWN SHUTDOWN CONTROL TRACKING APPLICATION INFORMATION SELECTING THE INPUT CAPACITOR OUTPUT LC FILTER SELECTING THE MOSFETS SETTING THE CURRENT LIMIT ACCURATE CURRENT-LIMIT SENSING FEEDBACK VOLTAGE DIVIDER COMPENSATING THE VOLTAGE MODE BUCK REGULATOR Type II Compensator Type III Compensator SOFT START SWITCHING NOISE AND OVERSHOOT REDUCTION VOLTAGE TRACKING COINCIDENT TRACKING RATIOMETRIC TRACKING THERMAL CONSIDERATIONS PCB LAYOUT GUIDELINE RECOMMENDED COMPONENT MANUFACTURERS APPLICATION CIRCUITS OUTLINE DIMENSIONS ORDERING GUIDE