Datasheet LTM4676A (Analog Devices) - 8

LTM4676A
elecTrical characTerisTics The
l
denotes the specifications which apply over the specified internal operating temperature range (Note 2). Specified as each individual output channel (Note 4). TA = 25°C, VIN = 12V, RUNn = 5V, FREQUENCY_SWITCH = 500kHz and VOUTn commanded to 1.000V unless otherwise noted. Configured with factory-default EEPROM settings and per Test Circuit 1, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
TRB-CH-ACC(ON) Channel Temperature READ_TEMPERATURE_1n, Channels 0 and 1, Within ±3°C of Reading TUE, Switching Action On PWM Active, RUNn = 5V (Note 12) TRB-CTRL-ACC(ON) Control IC Die READ_TEMPERATURE_2, PWM Active, RUN0 = RUN1 = 5V Within ±1°C of Reading Temperature TUE, (Note 12) Switching Action On tCONVERT-TEMP-RB Temperature Readback MFR_ADC_CONTROL = 0x00 (Notes 9, 15) 90 ms Update Rate MFR_ADC_CONTROL = 0x06 or 0x0A (Notes 9, 15) 8 ms
INTVCC Regulator
VINTVCC Internal VCC Voltage No 6V ≤ VIN ≤ 26.5V 4.8 5 5.2 V Load ∆VINTVCC(LOAD) INTVCC Load Regulation 0mA ≤ IINTVCC ≤ 50mA 0.5 ±2 % VINTVCC
VDD33 Regulator
VVDD33 Internal VDD33 Voltage 3.2 3.3 3.4 V ILIM(VDD33) VDD33 Current Limit VDD33 Electrically Short-Circuited to GND 70 mA VVDD33_OV VDD33 Overvoltage (Note 15) 3.5 V Threshold VVDD33_UV VDD33 Undervoltage (Note 15) 3.1 V Threshold
VDD25 Regulator
VVDD25 Internal VDD25 Voltage 2.5 V ILIM(VDD25) VDD25 Current Limit VDD25 Electrically Short-Circuited to GND 50 mA
Oscillator and Phase-Locked Loop (PLL)
fOSC Oscillator Frequency FREQUENCY_SWITCH = 500kHz (0xFBE8) l ±7.5 % Accuracy 250kHz ≤ FREQUENCY_SWITCH ≤ 1MHz (Note 15) ±7.5 % fSYNC PLL SYNC Capture Range FREQUENCY_SWITCH Set to Frequency Slave Mode (0x0000); l 225 1100 kHz MFR_CONFIG_ALL[4] = 1b; SYNC Driven by External Clock; 3.3VOUT VTH,SYNC SYNC Input Threshold VSYNC Rising (Note 15) 1.5 V VSYNC Falling (Note 15) 1 V VOL,SYNC SYNC Low Output ISYNC = 3mA l 0.3 0.4 V Voltage ISYNC SYNC Leakage Current in 0V ≤ VSYNC ≤ 3.6V l ±5 µA Frequency Slave Mode MFR_CONFIG_ALL[4] = 1b θSYNC-θ0 SYNC-to-Channel 0 (Note 15) Phase Relationship, Lag MFR_PWM_CONFIG[2:0] = 000b, 01Xb 0 Deg from Falling Edge of Sync MFR_PWM_CONFIG[2:0] = 101b 60 Deg to Rising Edge of Top MFR_PWM_CONFIG[2:0] = 001b 90 Deg MOSFET (MT0) Gate MFR_PWM_CONFIG[2:0] = 1X0b 120 Deg θSYNC-θ1 SYNC-to-Channel 1 (Note 15) Phase Relationship, Lag MFR_PWM_CONFIG[2:0] = 011b 120 Deg from Falling Edge of Sync MFR_PWM_CONFIG[2:0] = 000b 180 Deg to Rising Edge of Top MFR_PWM_CONFIG[2:0] = 010b, 10Xb 240 Deg MOSFET (MT1) Gate MFR_PWM_CONFIG[2:0] = 001b 270 Deg MFR_PWM_CONFIG[2:0] = 110b 300 Deg 4676afa 8 For more information www.linear.com/LTM4676A Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Simplified Block Diagram Decoupling Requirements Functional Diagram Test Circuits Operation Power Module Introduction Power Module Configurability and Readback Data Time-Averaged and Peak Readback Data Power Module Overview EEPROM Serial Interface Device Addressing Fault Detection and Handling Responses to VOUT and IOUT Faults Responses to Timing Faults Responses to SVIN OV Faults Responses to OT/UT Faults Responses to External Faults Fault Logging Bus Timeout Protection PMBus Command Summary PMBus Commands VIN to VOUT Step-Down Ratios Input Capacitors Output Capacitors Light Load Current Operation Switching Frequency and Phase 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 RCONFIG Pin-Straps (External Resistor Configuration Pins) Voltage Selection Connecting the USB to the I2C/SMBus/PMBus Controller to the LTM4676A In System LTpowerPlay: An Interactive GUI for Digital Power System Management PMBus Communication and Command Processing Thermal Considerations and Output Current Derating EMI Performance Safety Considerations Layout Checklist/Example Typical Applications Appendix A Similarity Between PMBus, SMBus and I2C 2-Wire Interface Appendix B PMBus Serial Digital Interface Appendix C: PMBus Command Details Addressing and Write Protect General Configuration Registers On/Off/Margin PWM Config Voltage Current Temperature Timing Fault Response Fault Sharing Scratchpad Identification Fault Warning and Status Telemetry NVM (EEPROM) Memory Commands Package Description Package Photograph Package Description Revision History Typical Application Design Resources Related Parts