LTC2974 Commands

Name Code Protocol Format Mask Writable Readable Description Fields
PAGE 0x00 WriteByte ReadByte HEX True True
OPERATION 0x01 WriteByte ReadByte FIELD True True
Name Description Bits
Operation_control 7:6
Operation_margin 5:4
Operation_fault 3:2
Operation_reserved 1:0
ON_OFF_CONFIG 0x02 WriteByte ReadByte FIELD True True
Name Description Bits
On_off_config_reserved 7:5
On_off_config_controlled_on 4
On_off_config_use_pmbus 3
On_off_config_use_control 2
On_off_config_control_pol 1
On_off_config_control_fast_off 0
CLEAR_FAULTS 0x03 Send HEX FMT True False
WRITE_PROTECT 0x10 WriteByte ReadByte HEX True True
STORE_USER_ALL 0x15 Send HEX FMT True False
RESTORE_USER_ALL 0x16 Send HEX FMT True False
CAPABILITY 0x19 ReadByte FIELD FMT False True
Name Description Bits
Capability_pec 7
Capability_scl_max 6
Capability_smb_alert 5
Capability_reserved 4:0
VOUT_MODE 0x20 ReadByte FIELD FMT False True
Name Description Bits
Vout_mode_type 7:5
Vout_mode_parameter 4:0
VOUT_COMMAND 0x21 WriteWord ReadWord L16 True True
VOUT_MAX 0x24 WriteWord ReadWord L16 True True
VOUT_MARGIN_HIGH 0x25 WriteWord ReadWord L16 True True
VOUT_MARGIN_LOW 0x26 WriteWord ReadWord L16 True True
VIN_ON 0x35 WriteWord ReadWord L11 True True
VIN_OFF 0x36 WriteWord ReadWord L11 True True
IOUT_CAL_GAIN 0x38 WriteWord ReadWord L11 True True
VOUT_OV_FAULT_LIMIT 0x40 WriteWord ReadWord L16 True True
VOUT_OV_FAULT_RESPONSE 0x41 WriteByte ReadByte FIELD True True
Name Description Bits
Vout_ov_fault_response_action 7:6
Vout_ov_fault_response_retry 5:3
Vout_ov_fault_response_delay 2:0
VOUT_OV_WARN_LIMIT 0x42 WriteWord ReadWord L16 True True
VOUT_UV_WARN_LIMIT 0x43 WriteWord ReadWord L16 True True
VOUT_UV_FAULT_LIMIT 0x44 WriteWord ReadWord L16 True True
VOUT_UV_FAULT_RESPONSE 0x45 WriteByte ReadByte FIELD True True
Name Description Bits
Vout_uv_fault_response_action 7:6
Vout_uv_fault_response_retry 5:3
Vout_uv_fault_response_delay 2:0
IOUT_OC_FAULT_LIMIT 0x46 WriteWord ReadWord L11 True True
IOUT_OC_FAULT_RESPONSE 0x47 WriteByte ReadByte FIELD True True
Name Description Bits
Vout_oc_fault_response_action 7:6
Vout_oc_fault_response_retry 5:3
Vout_oc_fault_response_delay 2:0
IOUT_OC_WARN_LIMIT 0x4A WriteWord ReadWord L11 True True
IOUT_UC_FAULT_LIMIT 0x4B WriteWord ReadWord L11 True True
IOUT_UC_FAULT_RESPONSE 0x4C WriteByte ReadByte FIELD True True
Name Description Bits
Vout_uc_fault_response_action 7:6
Vout_uc_fault_response_retry 5:3
Vout_uc_fault_response_delay 2:0
OT_FAULT_LIMIT 0x4F WriteWord ReadWord L11 True True
OT_FAULT_RESPONSE 0x50 WriteByte ReadByte FIELD True True
Name Description Bits
Vout_Ot_fault_response_action 7:6
Vout_Ot_fault_response_retry 5:3
Vout_Ot_fault_response_delay 2:0
OT_WARN_LIMIT 0x51 WriteWord ReadWord L11 True True
UT_WARN_LIMIT 0x52 WriteWord ReadWord L11 True True
UT_FAULT_LIMIT 0x53 WriteWord ReadWord L11 True True
UT_FAULT_RESPONSE 0x54 WriteByte ReadByte FIELD True True
Name Description Bits
Vout_Ut_fault_response_action 7:6
Vout_Ut_fault_response_retry 5:3
Vout_Ut_fault_response_delay 2:0
VIN_OV_FAULT_LIMIT 0x55 WriteWord ReadWord L11 True True
VIN_OV_FAULT_RESPONSE 0x56 WriteByte ReadByte FIELD True True
Name Description Bits
Vout_ov_fault_response_action 7:6
Vout_ov_fault_response_retry 5:3
Vout_ov_fault_response_delay 2:0
VIN_OV_WARN_LIMIT 0x57 WriteWord ReadWord L11 True True
VIN_UV_WARN_LIMIT 0x58 WriteWord ReadWord L11 True True
VIN_UV_FAULT_LIMIT 0x59 WriteWord ReadWord L11 True True
VIN_UV_FAULT_RESPONSE 0x5A WriteByte ReadByte FIELD True True
Name Description Bits
Vin_uv_fault_response_action 7:6
Vin_uv_fault_response_retry 5:3
Vin_uv_fault_response_delay 2:0
POWER_GOOD_ON 0x5E WriteWord ReadWord L16 True True
POWER_GOOD_OFF 0x5F WriteWord ReadWord L16 True True
TON_DELAY 0x60 WriteWord ReadWord L11 True True
TON_RISE 0x61 WriteWord ReadWord L11 True True
TON_MAX_FAULT_LIMIT 0x62 WriteWord ReadWord L11 True True
TON_MAX_FAULT_RESPONSE 0x63 WriteByte ReadByte FIELD True True
Name Description Bits
Ton_max_fault_response_action 7:6
Ton_max_fault_response_retry 5:3
TOFF_DELAY 0x64 WriteWord ReadWord L11 True True
STATUS_BYTE 0x78 ReadByte FIELD FMT False True
Name Description Bits
Status_byte_busy 7
Status_byte_off 6
Status_byte_vout_ov 5
Status_byte_iout_oc 4
Status_byte_vin_uv 3
Status_byte_temp 2
Status_byte_cml 1
Status_byte_high_byte 0
STATUS_WORD 0x79 ReadWord FIELD FMT False True
Name Description Bits
Status_word_vout 15
Status_word_iout_or_pout 14
Status_word_input 13
Status_word_mfr 12
Status_word_power_not_good 11
Status_word_reserved 10:8
Status_word_busy 7
Status_word_off 6
Status_word_vout_ov 5
Status_word_iout_oc 4
Status_word_vin_uv 3
Status_word_temp 2
Status_word_cml 1
Status_word_high_byte 0
STATUS_VOUT 0x7A ReadByte FIELD FMT False True
Name Description Bits
Status_vout_ov_fault 7
Status_vout_ov_warn 6
Status_vout_uv_warn 5
Status_vout_uv_fault 4
Status_vout_max_fault 3
Status_vout_ton_max_fault 2
Status_vout_toff_max_warn 1
Status_vout_track_error 0
STATUS_IOUT 0x7B ReadByte FIELD FMT False True
Name Description Bits
Status_iout_oc_fault 7
Status_iout_reserved 6
Status_iout_oc_warn 5
Status_iout_uc_fault 4
Status_iout_ishare_fault 3
Status_pout_at_limit 2
Status_pout_op_fault 1
Status_pout_op_warn 0
STATUS_INPUT 0x7C ReadByte FIELD FMT False True
Name Description Bits
Status_input_ov_fault 7
Status_input_ov_warn 6
Status_input_uv_warn 5
Status_input_uv_fault 4
Status_input_off 3
Status_input_oc_fault 2
Status_input_oc_warn 1
Status_input_op_warn 0
STATUS_TEMPERATURE 0x7D ReadByte FIELD FMT False True
Name Description Bits
Status_temperature_ot_fault 7
Status_temperature_ot_warn 6
Status_temperature_ut_warn 5
Status_temperature_ut_fault 4
Status_temperature_reserved 3:1
Status_temperature_tc_warn 0
STATUS_CML 0x7E ReadByte FIELD FMT False True
Name Description Bits
Status_cml_cmd_fault 7
Status_cml_data_fault 6
Status_cml_pec_fault 5
Status_cml_memory_fault 4
Status_cml_processor_fault 3
Status_cml_reserved 2
Status_cml_pmbus_fault 1
Status_cml_other_fault 0
STATUS_MFR_SPECIFIC 0x80 ReadByte FIELD FMT False True
Name Description Bits
Status_mfr_discharge 7
Status_mfr_fault1_in 6
Status_mfr_fault0_in 5
Status_mfr_servo_target_reached 4
Status_mfr_dac_connected 3
Status_mfr_dac_saturated 2
Status_mfr_vien_faulted_off 1
Status_mfr_watchdog_fault 0
READ_VIN 0x88 ReadWord L11 FMT False True
READ_VOUT 0x8B ReadWord L16 FMT False True
READ_IOUT 0x8C ReadWord L11 FMT False True
READ_TEMPERATURE_1 0x8D ReadWord L11 FMT False True
READ_TEMPERATURE_2 0x8E ReadWord L11 FMT False True
READ_POUT 0x96 ReadWord L11 FMT False True
PMBUS_REVISION 0x98 ReadByte HEX FMT False True
USER_DATA_00 0xB0 WriteWord ReadWord HEX True True
USER_DATA_01 0xB1 WriteWord ReadWord HEX True True
USER_DATA_02 0xB2 WriteWord ReadWord HEX True True
USER_DATA_03 0xB3 WriteWord ReadWord HEX True True
USER_DATA_04 0xB4 WriteWord ReadWord HEX True True
MFR_LTC_RESERVED_1 0xB5 WriteWord ReadWord HEX True True
MFR_T_SELF_HEAT 0xB8 ReadWord L11 FMT False True
MFR_IOUT_CAL_GAIN_TAU_INV 0xB9 WriteWord ReadWord L11 True True
MFR_IOUT_CAL_GAIN_THETA 0xBA WriteWord ReadWord L11 True True
MFR_READ_IOUT 0xBB ReadWord HEX FMT False True
MFR_LTC_RESERVED_2 0xBC WriteWord ReadWord HEX True True
MFR_EE_UNLOCK 0xBD WriteByte ReadByte HEX True True
MFR_EE_ERASE 0xBE WriteByte ReadByte HEX True True
MFR_EE_DATA 0xBF WriteWord ReadWord HEX True True
MFR_CONFIG_LTC2974 0xD0 WriteWord ReadWord FIELD True True
Name Description Bits
Mfr_config_reserved 15
Mfr_config_negative_rail 14
Mfr_config_controln_sel 13:12
Mfr_config_fast_servo_off 11
Mfr_config_supervisor_resolution 10
Mfr_config_reserved_bit9 9
Mfr_config_reserved_bit8 8
Mfr_config_servo_continuous 7
Mfr_config_servo_on_warn 6
Mfr_config_dac_mode 5:4
Mfr_config_voen_wpu_en 3
Mfr_config_voen_wpd_en 2
Mfr_config_dac_gain 1
Mfr_config_dac_pol 0
MFR_CONFIG_ALL_LTC2974 0xD1 WriteWord ReadWord FIELD True True
Name Description Bits
Mfr_config_all_reserved 15:12
Mfr_config_all_pwrgd_includes_uv 11
Mfr_config_all_fast_fault_log 10
Mfr_config_all_control3_pol 9
Mfr_config_all_control2_pol 8
Mfr_config_all_data_log_en 7
Mfr_config_all_vin_on_clr_faults_en 6
Mfr_config_all_control1_pol 5
Mfr_config_all_control0_pol 4
Mfr_config_all_vin_share_en 3
Mfr_config_all_pec_en 2
Mfr_config_all_pmbus_timeout 1
Mfr_config_all_vien_wpu_dis 0
MFR_FAULTB0_PROPAGATE 0xD2 WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_faultbz0_propagate_reserved 7:1
Mfr_faultbz0_propagate 0
MFR_FAULTB1_PROPAGATE 0xD3 WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_faultbz1_propagate_reserved 7:1
Mfr_faultbz1_propagate 0
MFR_PWRGD_EN 0xD4 WriteWord ReadWord FIELD True True
Name Description Bits
Mfr_pwrgd_en_reserved 15:9
Mfr_pwrgd_en_wdog 8
Mfr_pwrgd_en_reserved7 7
Mfr_pwrgd_en_reserved6 6
Mfr_pwrgd_en_reserved5 5
Mfr_pwrgd_en_reserved4 4
Mfr_pwrgd_en_chan3 3
Mfr_pwrgd_en_chan2 2
Mfr_pwrgd_en_chan1 1
Mfr_pwrgd_en_chan0 0
MFR_FAULTB0_RESPONSE 0xD5 WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_faultb00_response_reserved 7:4
Mfr_faultb00_response_chan3 3
Mfr_faultb00_response_chan2 2
Mfr_faultb00_response_chan1 1
Mfr_faultb00_response_chan0 0
MFR_FAULTB1_RESPONSE 0xD6 WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_faultb01_response_reserved 7:4
Mfr_faultb01_response_chan3 3
Mfr_faultb01_response_chan2 2
Mfr_faultb01_response_chan1 1
Mfr_faultb01_response_chan0 0
MFR_IOUT_PEAK 0xD7 ReadWord L11 FMT False True
MFR_IOUT_MIN 0xD8 ReadWord L11 FMT False True
MFR_CONFIG2_LTC2974 0xD9 WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_vien_oc_fault_response_chan3 7
Mfr_vien_oc_fault_response_chan2 6
Mfr_vien_oc_fault_response_chan1 5
Mfr_vien_oc_fault_response_chan0 4
Mfr_vien_ov_fault_response_chan3 3
Mfr_vien_ov_fault_response_chan2 2
Mfr_vien_ov_fault_response_chan1 1
Mfr_vien_ov_fault_response_chan0 0
MFR_CONFIG3_LTC2974 0xDA WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_vien_uc_fault_response_chan3 7
Mfr_vien_uc_fault_response_chan2 6
Mfr_vien_uc_fault_response_chan1 5
Mfr_vien_uc_fault_response_chan0 4
Mfr_vien_uv_fault_response_chan3 3
Mfr_vien_uv_fault_response_chan2 2
Mfr_vien_uv_fault_response_chan1 1
Mfr_vien_uv_fault_response_chan0 0
MFR_RETRY_DELAY 0xDB WriteWord ReadWord L11 True True
MFR_RESTART_DELAY 0xDC WriteWord ReadWord L11 True True
MFR_VOUT_PEAK 0xDD ReadWord L16 FMT False True
MFR_VIN_PEAK 0xDE ReadWord L11 FMT False True
MFR_TEMPERATURE_1_PEAK 0xDF ReadWord L11 FMT False True
MFR_DAC 0xE0 WriteWord ReadWord FIELD True True
Name Description Bits
Mfr_dac_reserved 15:10
Mfr_dac_direct_val 9:0
MFR_POWER_GOOD_ASSERTION_DELAY 0xE1 WriteWord ReadWord L11 True True
MFR_WATCHDOG_T_FIRST 0xE2 WriteWord ReadWord L11 True True
MFR_WATCHDOG_T 0xE3 WriteWord ReadWord L11 True True
MFR_PAGE_FF_MASK 0xE4 WriteByte ReadByte HEX True True
MFR_PADS 0xE5 WriteWord ReadWord FIELD True True
Name Description Bits
Mfr_pads_pwrgd_drive 15
Mfr_pads_alertb_drive 14
Mfr_pads_faultb_drive 13:10
Mfr_pads_asel1 9:8
Mfr_pads_asel0 7:6
Mfr_pads_control1 5
Mfr_pads_control0 4
Mfr_pads_faultb 3:2
Mfr_pads_control2 1
Mfr_pads_control3 0
MFR_I2C_BASE_ADDRESS 0xE6 WriteByte ReadByte HEX True True
MFR_SPECIAL_ID 0xE7 ReadWord HEX FMT False True
MFR_SPECIAL_LOT 0xE8 ReadByte HEX FMT False True
MFR_VOUT_DISCHARGE_THRESHOLD 0xE9 WriteWord ReadWord L11 True True
MFR_FAULT_LOG_STORE 0xEA Send HEX FMT True False
MFR_FAULT_LOG_RESTORE 0xEB Send HEX FMT True False
MFR_FAULT_LOG_CLEAR 0xEC Send HEX FMT True False
MFR_FAULT_LOG_STATUS 0xED ReadByte FIELD FMT False True
Name Description Bits
Mfr_data_log_status 7:2
Mfr_data_log_status_ram_lock 1
Mfr_data_log_status_eeprom_lock 0
MFR_FAULT_LOG 0xEE ReadBlock HEX FMT False True
MFR_COMMON 0xEF WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_common_alertb_deasserted 7
Mfr_common_device_not_busy 6
Mfr_common_share_clk 1
Mfr_common_write_protect 0
MFR_IOUT_CAL_GAIN_TC 0xF6 WriteWord ReadWord HEX True True
MFR_RETRY_COUNT 0xF7 WriteByte ReadByte FIELD True True
Name Description Bits
Mfr_retry_count_reserved 7:3
Mfr_retry_count_number 2:0
MFR_TEMP_1_GAIN 0xF8 WriteWord ReadWord HEX True True
MFR_TEMP_1_OFFSET 0xF9 WriteWord ReadWord L11 True True
MFR_IOUT_SENSE_VOLTAGE 0xFA ReadWord L16 FMT False True
MFR_VOUT_MIN 0xFB ReadWord L16 FMT False True
MFR_VIN_MIN 0xFC ReadWord L11 FMT False True
MFR_TEMPERATURE_1_MIN 0xFD ReadWord L11 FMT False True