LTC2977 datasheet(94/138 Pages) AD

94 / 138 page

LTM4664A

Rev. 0

For more information www.analog.com

ON_OFF_CONFIG

The ON_OFF_CONFIG command specifies the combination of RUNn pin input state and PMBus commands needed to

turn the PWM channel on and off.

Supported Values:

VALUE

MEANING

0x1F

OPERATION value and RUNn pin must both command the device to start/run. Device executes immediate off when commanded off.

0x1E

OPERATION value and RUNn pin must both command the device to start/run. Device uses TOFF_ command values when commanded off.

0x17

RUNn pin control with immediate off when commanded off. OPERATION on/off control ignored.

0x16

RUNn pin control using TOFF_ command values when commanded off. OPERATION on/off control ignored.

Programming an unsupported ON_OFF_CONFIG value will generate a CML fault and the command will be ignored.

This command has one data byte.

OPERATION

The OPERATION command is used to turn the unit on and off in conjunction with the input from the RUNn pins. It

is also used to cause the unit to set the output voltage to the upper or lower MARGIN VOLTAGEs. The unit stays in

the commanded operating mode until a subsequent OPERATION command or change in the state of the RUNn pin

instructs the device to change to another mode. If the part is stored in the MARGIN_LOW/HIGH state, the next RESET

or POWER_ON cycle will ramp to that state. If the OPERATION command is modified, for example ON is changed

to MARGIN_LOW, the output will move at a fixed slope set by the VOUT_TRANSITION_RATE. The default operation

command is sequence off. If VIN is applied to a part with factory default programming and the VOUT_CONFIG resistor

configuration pins are not installed, the outputs will be commanded off.

The part defaults to the Sequence Off state.

This command has one data byte.

Supported Values:

VALUE

MEANING

0xA8

Margin high.

0x98

Margin low.

0x80

On (VOUT back to nominal even if bit 3 of ON_OFF_CONFIG is not set).

0x40*

Soft off (with sequencing).

0x00*

Immediate off (no sequencing).

*Device does not respond to these commands if bit 3 of ON_OFF_CONFIG is not set.

Programming an unsupported OPERATION value will generate a CML fault and the command will be ignored.

This command has one data byte.

MFR_RESET

This command provides a means to reset the LTM4664A PSM from the serial bus. This forces the LTM4664A PSM

to turn off both PWM channels, load the operating memory from internal EEPROM, clear all faults and then perform a

soft-start of both PWM channels, if enabled.

This write-only command has no data bytes.

PMBus COMMAND DETAILS

LTC2977 Datasheet(PDF) 94 Page - Analog Devices

LTC2977 Datasheet(HTML) 94 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL