link to page 84 LTM4664 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the internal operatingjunction temperature. TA = 25°C, VINS1 = 48V, and RUNn= 5V where n= stage # unless otherwise noted. See Figure 46configurationfor setup. (Note 3)SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS M5-M8 RDS-ON Stage 2 MOSFET On Resistance VGS = 5V (Note 16) 10 mΩ VOUT1, (AC) Output Ripple Voltage VOUT1 = 24V, 0A to 3A VINS1 = 48V, FREQS1 = 100kHz 150 mVpk-pk CINB1 = 33µF (Input Bulk Capacitor) CIN1 = 2.2µF 100V Ceramic, CFLY1 = 10µF 50V X6 COUT1 = 10µF 50V VOUT2, (AC) Output Ripple Voltage VOUT2 = 12V, 0A to 6A 50 mVpk-pk VINS2 = 12V, FREQS2 = 200kHz CINB2 = 33µF (Input Bulk Capacitor) CIN2 = 10µF 50V Ceramic, CFLY2 = 22µF 25V X6, COUT2 = 22µF 25V tSTART Stage 1 Turn-on Time VOUT1 = 0V at Start Up to 24V, 0A, VINS1 = 48V, From RUN 1 FREQS1 = 100kHz CINB1 = 33µF (Input Bulk Capacitor) 40 msec CIN1 = 2.2µF 100V Ceramic, CFLY1 = 10µF 50V X6 COUT1 = 10µF 50V, CTIMERS1 = 0.22µF tSTART Stage 2 Turn-on Time Stage 2 VOUT2 = 0V at Start Up to 12V, 0A, VINS2 = 24V, 75 msec From RUN 2 FREQS2 = 200kHz CINB2 = 33µF (Input Bulk Capacitor) CIN1 = 2.2µF 100V Ceramic, CFLY1 = 22µF, 25V X6 COUT2 = 22µF 25V, CTIMERS2 = 0.47µF HYS_PRGMn and FAULTSn VFAULTSn FAULT Voltage Low IFAULT = 2mA 0.2 0.4 V IFAULT_LEAKSn FAULT Leakage Current VFAULT = 5V ±1 µA IHYS_PRGMSn HYS_PRGM Setting Current l 9 10 11 µA VFAULTSn VOUTSn Fault Trip Level VINSn = 24V, VOUTn, HYS_PRGMSn = 0V, VOUTSn Ramp Up l 12.2 12.3 12.45 V VOUTSn Ramp Down l 11.6 11.7 11.8 V VFAULTSn VOUTSn Fault Trip Level VINSn = 24V, VOUTn, HYS_PRGMSn = 5V, VOUTSn Ramp Up l 12.7 12.8 12.9 V VOUTSn Ramp Down l 11.1 11.2 11.3 V VFAULTSn VOUTSn Fault Trip Level VINSn = 24V, VOUTn, HYS_PRGMSn = 2.4V, VOUTSn Ramp Up l 14.15 14.3 14.45 V VOUTSn Ramp Down l 9.5 9.65 9.8 V UV COMPARATORn and PGOODn VUVTHSSn Undervoltage Threshold UV Pin Voltage Rising 0.99 1.01 1.03 V VHYS_PRGMSn Undervoltage Hysteresis 120 mV VPGOODSn PGOOD Voltage Low IPGOOD = 2mA 0.35 0.5 V IPGOODSn_LEAK PGOOD Leakage Current VPGOOD = 5V ±1 µA TimerSn TimerSn Current ITIMERn VTIMER < 0.5V or VTIMER > 1.2V 3.5 µA 0.5V < VTIMER < 1.2V 7 µA Rev. 0 For more information www.analog.com 7 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics 4:1 Divider Block Diagram Dual 25A Power System Management (PSM) Block Diagram 4:1 Divider Operation 4:1 Divider Description Main Control INTVCCS1,2/EXTVCCS1,2 Power Start-Up and Shutdown Fault Protection and Thermal Shutdown High Side Current Sensing Frequency Selection Power Good and UV (PGOODSn and UVSn pins) Additional Overvoltage Protection 4:1 Divider Application Information Voltage Divider Pre-Balance Before Switching Overcurrent Protection Window Comparator Programming Effective Open Loop Output Resistance and Load Regulation Undervoltage Lockout Fault Response and Timer Programming Design Example Dual 25A PSM Operation PSM Section Overview, Major Features EEPROM with ECC Power-Up and Initialization Soft-Start Time-Based Sequencing Voltage-Based Sequencing Shutdown Light-Load Current Operation Switching Frequency and Phase PWM Loop Compensation Output Voltage Sensing INTVCC/EXTVCC Power Output Current Sensing and Sub Milliohm DCR Current Sensing Input Current Sensing PolyPhase Load Sharing External/Internal Temperature Sense RCONFIG (Resistor Configuration) Pins Fault Detection and Handling Status Registers and ALERT Masking Mapping Faults to FAULT Pins Power Good Pins CRC Protection Serial Interface Communication Protection Device Addressing Responses to VOUT and IIN/IOUT Faults Output Overvoltage Fault Response Output Undervoltage Response Peak Output Overcurrent Fault Response Responses to Timing Faults Responses to VIN OV Faults Responses to OT/UT Faults Internal Overtemperature Fault Response External Overtemperature and Undertemperature Fault Response Responses to Input Overcurrent and Output Undercurrent Faults Responses to External Faults Fault Logging Bus Timeout Protection Similarity Between PMBus, SMBus and I2C 2-Wire Interface PMBus Serial Digital Interface Figure 11 thru Figure 28 PMBus Protocols PMBus Command Summary PMBus Commands Dual 25A PSM Applications Information VIN to VOUT Step-Down Ratios Input Capacitors Output Capacitors Light Load Current Operation Switching Frequency and Phase Output Current Limit Programming Minimum On-Time Considerations Variable Delay Time, Soft-Start and Output Voltage Ramping Digital Servo Mode Soft Off (Sequenced Off) Undervoltage Lockout Fault Detection and Handling Open-Drain Pins Phase-Locked Loop and Frequency Synchronization Input Current Sense Amplifier Programmable Loop Compensation Checking Transient Response PolyPhase® Configuration Connecting the USB to I2C/SMBus/PMBus Controller to the LTM4664 In-System LTpowerPlay: An Interactive GUI for Digital Power PMBus Communication and Command Processing Thermal Considerations and Output Current Derating Table 10 and Table 11: Output Current Derating (Based on Demo Board) Dual 25A PSM Applications Information–Derating Curves EMI Performance Safety Considerations Layout Checklist/Example Typical Applications PMBus Command Details Addressing and Write Protect General Configuration Commands On/Off/Margin PWM Configuration Voltage Input Voltage and Limits Output Voltage and Limits Output Current and Limits Input Current and Limits Temperature External Temperature Calibration Timing Timing—On Sequence/Ramp Timing—Off Sequence/Ramp Precondition for Restart Fault Response Fault Responses All Faults Fault Responses Input Voltage Fault Responses Output Voltage Fault Responses Output Current Fault Responses IC Temperature Fault Responses External Temperature Fault Sharing Fault Sharing Propagation Fault Sharing Response Scratchpad Identification Fault Warning and Status Telemetry NVM Memory Commands Store/Restore Fault Logging Block Memory Write/Read Package Description Typical Applications Related Parts