link to page 27 ADP1850Data SheetSW1OUTPUT RESPONSE11PGOOD1VCCO (CH3)8A TO 13A STEP LOAD2VOUT, PRELOADED (CH4)34VIN = 12V VOUT = 3.3V4 011 CH1 20mVBCH1 10VCH2 2VM10msA CH2 3.76V 014 WM200µsA CH4 11.5ACH4 5A Ω 09440- CH3 2VCH4 2V Ω 09440- Figure 10. Step Load Transient of Figure 44 Figure 13. Thermal Shutdown Waveform 0.5REFERENCED AT VIN = 2.75V0DH11%) –0.5DL1(2f SW600kHzN I –1.0VOUT1E300kHz–1.53IL1CHANG4VIN = 12V–2.0VOUT = 1.8V OUTPUT PRECHARGED TO 1V850kHz–2.5CH1 5VCH2 5VM1msA CH1 2.4V 012 3579111315171921 015 CH3 1VCH4 1A Ω 09440- VIN (V) 09440- Figure 11. Soft Start into Precharged Output Figure 14. Change in fSW vs. VIN 2.0VIN = 12V; REFERENCED AT 25°C1.51.01SW%)0.5(VOUT (CH3)f SW0N I E –0.5–1.0CHANGENSS (CH4)–1.53 2 4–2.0CSS = 100nF–2.5CH1 10VCH2 2VM10msA CH2 1.52V 013 –40–1510356085110135 016 CH3 1VCH4 1V 09440- TEMPERATURE (°C) 09440- Figure 12. Enable Start-Up Function Figure 15. fSW vs. Temperature Rev. C | Page 10 of 32 Document Outline Features Applications General Description Typical Operation Circuit Revision History Specifications Absolute Maximum Ratings ESD Caution Simplified Block Diagram Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Control Architecture Oscillator Frequency Modes of Operation Synchronization Synchronous Rectifier and Dead Time Input Undervoltage Lockout Internal Linear Regulator Overvoltage Protection Power Good Short-Circuit and Current-Limit Protection Shutdown Control Thermal Overload Protection Applications Information Setting the Output Voltage Soft Start Setting the Current Limit Accurate Current-Limit Sensing Setting the Slope Compensation Setting the Current Sense Gain Input Capacitor Selection Input Filter Boost Capacitor Selection Inductor Selection Output Capacitor Selection MOSFET Selection Loop Compensation (Single Phase Operation) Configuration and Loop Compensation (Dual-Phase Operation) Switching Noise and Overshoot Reduction Voltage Tracking Coincident Tracking Ratiometric Tracking Indepdendent Power Stage Input Voltage PCB Layout Guidelines MOSFETs, Input Bulk Capacitor, and Bypass Capacitor High Current and Current Sense Paths Signal Paths PGND Plane Feedback and Current-Limit Sense Paths Switch Node Gate Driver Paths Output Capacitors Typical Operating Circuits Outline Dimensions Ordering Guide