Техническая Спецификация для Linear Technology LTC2977 Demo Board: Octal Power Supply Manager [Requires DC1613] DC2028A DC2028A

Модели

DC2028A

LTC2977

2977fa

For more information

www.linear.com/LTC2977

Table oF conTenTs

MFR_FAULTB00_RESPONSE, MFR_FAULTB01_

RESPONSE, MFR_FAULTB10_RESPONSE and

MFR_FAULTB11_RESPONSE ..............................52

MFR_VINEN_OV_FAULT_RESPONSE .................53

MFR_VINEN_UV_FAULT_RESPONSE .................54

MFR_RETRY_COUNT .........................................55

MFR_RETRY_DELAY ..........................................55

MFR_RESTART_DELAY ......................................55

MFR_VOUT_PEAK ..............................................56

MFR_VIN_PEAK .................................................56

MFR_TEMPERATURE_PEAK ..............................56

MFR_DAC ...........................................................57

MFR_POWERGOOD_ASSERTION_DELAY .........57

MFR_PADS .........................................................58

MFR_SPECIAL_ID ..............................................59

MFR_SPECIAL_LOT ...........................................59

MFR_VOUT_DISCHARGE_THRESHOLD .............59

MFR_COMMON ..................................................60

USER_DATA_00, USER_DATA_01, USER_

DATA_02, USER_DATA_03, USER_DATA_04,

MFR_LTC_RESERVED_1 and MFR_LTC_

RESERVED_2 .....................................................60

MFR_VOUT_MIN ................................................61

MFR_VIN_MIN ...................................................61

MFR_TEMPERATURE_MIN ................................61

MFR_STATUS_2 .................................................62

MFR_TELEMETRY ..............................................63

Watchdog Operation ...............................................64

MFR_WATCHDOG_T_FIRST and MFR_

WATCHDOG_T ....................................................64

Bulk Programming the User EEPROM Space ..........65

MFR_EE_UNLOCK ..............................................65

MFR_EE_ERASE ................................................66

MFR_EE_DATA ...................................................66

Response When Part Is Busy .............................67

MFR_EE Erase and Write Programming Time ....67

Fault Log Operation ................................................67

MFR_FAULT_LOG_STORE .................................67

MFR_FAULT_LOG_RESTORE .............................67

MFR_FAULT_LOG_CLEAR ..................................68

MFR_FAULT_LOG_STATUS ................................68

MFR_FAULT_LOG ...............................................69

Applications Information ................................76

Overview .................................................................76

Powering the LTC2977............................................76

Setting Command Register Values .........................76

Sequence, Servo, Margin and Restart Operations ..76

Command Units On or Off ..................................76

On Sequencing ...................................................77

On State Operation .............................................77

Servo Modes ......................................................77

DAC Modes .........................................................77

Margining ...........................................................78

Off Sequencing ...................................................78

OUT

Off Threshold Voltage ................................78

Automatic Restart Via MFR_RESTART_DELAY

Command and CONTROLn pin ...........................78

Fault Management ..................................................78

Output Overvoltage and Undervoltage Faults .....78

Output Overvoltage and Undervoltage

Warnings ............................................................79

Configuring the V

IN_EN

Output ............................79

Multichannel Fault Management ........................81

Interconnect Between Multiple LTC2977’s ..............81

Application Circuits .................................................82

Trimming and Margining DC/DC Converters with

External Feedback Resistors...............................82

Four-Step Resistor Selection Procedure for DC/DC

Converters with External Feedback Resistors.....83

Trimming and Margining DC/DC Converters

with a TRIM Pin ..................................................84

Two-Step Resistor and DAC Full-Scale Voltage

Selection Procedure for DC/DC Converters

with a TRIM Pin ..................................................84

Measuring Current ..............................................84

Measuring Current with a Sense Resistor...........85

Measuring Current with Inductor DCR ................85

Single Phase Design Example ............................85

Measuring Multiphase Currents..........................85

Multiphase Design Example ...............................86

Anti-aliasing Filter Considerations ......................86

Sensing Negative Voltages .................................87

Connecting the DC1613 USB to I

C/SMBus/PMBus

Controller to the LTC2977 in System ......................87

Design Checklist .....................................................89

LTpowerPlay: An Interactive GUI for Power System

Managers ................................................................89

PCB Assembly and Layout Suggestions .................90

Bypass Capacitor Placement ..............................90

Exposed Pad Stencil Design ...............................90

PC Board Layout.................................................91

Unused ADC Sense Inputs ..................................91

Package Description .....................................92

Revision History ..........................................93

Typical Application .......................................94

Related Parts ..............................................94