Datasheet ADP1872, ADP1873 (Analog Devices) - 4

ManufacturerAnalog Devices
DescriptionSynchronous Current-Mode with Constant On-Time, PWM Buck Controller
Pages / Page40 / 4 — ADP1872/ADP1873. Data Sheet. Parameter. Symbol. Conditions. Min. Typ. …
RevisionB
File Format / SizePDF / 1.7 Mb
Document LanguageEnglish

ADP1872/ADP1873. Data Sheet. Parameter. Symbol. Conditions. Min. Typ. Max. Unit

ADP1872/ADP1873 Data Sheet Parameter Symbol Conditions Min Typ Max Unit

Model Line for this Datasheet

Text Version of Document

link to page 16 link to page 16 link to page 16 link to page 16 link to page 16 link to page 16 link to page 16 link to page 16 link to page 4 link to page 4 link to page 4 link to page 4 link to page 4 link to page 4
ADP1872/ADP1873 Data Sheet Parameter Symbol Conditions Min Typ Max Unit
OUTPUT DRIVER CHARACTERISTICS High-Side Driver Output Source Resistance ISOURCE = 1.5 A, 100 ns, positive pulse (0 V to 5 V) 2 3.5 Ω Output Sink Resistance ISINK = 1.5 A, 100 ns, negative pulse (5 V to 0 V) 0.8 2 Ω Rise Time2 tr, DRVH BST − SW = 4.4 V, CIN = 4.3 nF (see Figure 59) 25 ns Fall Time2 tf, DRVH BST − SW = 4.4 V, CIN = 4.3 nF (see Figure 60) 11 ns Low-Side Driver Output Source Resistance ISOURCE = 1.5 A, 100 ns, positive pulse (0 V to 5 V) 1.7 3 Ω Output Sink Resistance ISINK = 1.5 A, 100 ns, negative pulse (5 V to 0 V) 0.75 2 Ω Rise Time2 tr, DRVL VDD = 5.0 V, CIN = 4.3 nF (see Figure 60) 18 ns Fall Time2 tf, DRVL VDD = 5.0 V, CIN = 4.3 nF (see Figure 59) 16 ns Propagation Delays DRVL Fall to DRVH Rise2 ttpdh, DRVH BST − SW = 4.4 V (see Figure 59) 22 ns DRVH Fall to DRVL Rise2 ttpdh, DRVL BST − SW = 4.4 V (see Figure 60) 24 ns SW Leakage Current ISW, LEAK BST = 25 V, SW = 20 V, VDD = 5.5 V 110 µA Integrated Rectifier Channel Impedance ISINK = 10 mA 22 Ω PRECISION ENABLE THRESHOLD Logic High Level VIN = 2.9 V to 20 V, VDD = 2.75 V to 5.5 V 235 285 330 mV Enable Hysteresis VIN = 2.9 V to 20 V, VDD = 2.75 V to 5.5 V 35 mV COMP VOLTAGE COMP Clamp Low Voltage VCOMP (LOW) From disable state, release COMP/EN pin to enable 0.47 V device (2.75 V ≤ VDD ≤ 5.5 V) COMP Clamp High Voltage VCOMP (HIGH) (2.75 V ≤ VDD ≤ 5.5 V) 2.55 V COMP Zero Current Threshold VCOMP_ZCT (2.75 V ≤ VDD ≤ 5.5 V) 1.15 V THERMAL SHUTDOWN TTMSD Thermal Shutdown Threshold Rising temperature 155 °C Thermal Shutdown Hysteresis 15 °C Hiccup Current Limit Timing 6 ms 1 The maximum specified values are with the closed loop measured at 10% to 90% time points (see Figure 59 and Figure 60), CGATE = 4.3 nF and upper- and lower-side MOSFETs being Infineon BSC042N03MS G. 2 Not automatic test equipment (ATE) tested. Rev. B | Page 4 of 40 Document Outline Features Applications Typical Applications Circuit General Description Revision History Specifications Absolute Maximum Ratings Thermal Resistance Boundary Condition ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics ADP1872/ADP1873 Block Digram 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 (ADP1873) 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 Consideration Channel Conduction Loss MOSFET Driver Loss MOSFET Switching Loss Body 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 Application Circuits Dual-Input, 300 kHz High Current Application Circuit Single-Input, 600 kHz Application Circuit Dual-Input, 300 kHz High Current Application Circuit Outline Dimensions Ordering Guide