Datasheet

LTC2974
32
2974fc
For more information www.linear.com/LTC2974
MFR_CONFIG_LTC2974
This command is used to configure various manufacturer specific operating parameters for each channel.
MFR_CONFIG_LTC2974 Data Contents
BIT(S) SYMBOL OPERATION
b[15] Reserved Don’t care. Always returns 0.
b[14] Mfr_config_cascade_on Configures channel’s control pin for cascade sequence ON. There is no provision for cascade sequence
OFF. See description for time based sequence OFF options.
b[13:12] Mfr_config_controln_sel[1:0] Selects the active control pin input (CONTROL0 , CONTROL1, CONTROL2 or CONTROL3) for this channel.
0: Select CONTROL0 pin.
1: Select CONTROL1 pin.
2: Select CONTROL2 pin.
3: Select CONTROL3 pin.
b[11] Mfr_config_fast_servo_off Disables fast servo when margining or trimming output voltages:
0: fast-servo enabled.
1: fast-servo disabled.
b[10] Mfr_config_supervisor_resolution Selects voltage supervisor resolution:
0: high resolution = 4mV / LSB, range for V
VSENSEPn
– V
VSENSEMn
is 0 to 3.8V
1: low resolution = 8mV / LSB, range for V
VSENSEPn
– V
VSENSEMn
is 0 to 6.0V
b[9:8] Reserved Always returns 0.
b[7] Mfr_config_servo_continuous Select whether the UNIT should continuously servo VOUT after it has reached a new margin or nominal
target. Only applies when Mfr_ config _dac_mode = 00b.
0: Do not continuously servo VOUT after reaching initial target.
1: Continuously servo VOUT to target.
b[6] Mfr_config_servo_on_warn Control re-servo on warning feature. Only applies when Mfr_config_dac_mode = 00b and Mfr_config_
servo_continuous = 0.
0: Do not allow the unit to re-servo when a VOUT warning threshold is met or exceeded.
1: Allow the unit to re-servo VOUT to nominal target if
VOUT ≥ V(Vout_ov_warn_limit) or
VOUT ≤ V(Vout_uv_warn_limit).
b[5:4] Mfr_config_dac_mode Determines how DAC is used when channel is in the ON state and TON_RISE has elapsed.
00: Soft-connect (if needed) and servo to target.
01: DAC not connected.
10: DAC connected immediately using value from MFR_DAC command. If this is the configuration after a
reset or RESTORE_USER_ALL, MFR_DAC will be undefined and must be written to desired value.
11: DAC is soft-connected. After soft-connect is complete MFR_DAC may be written.
b[3] Mfr_config_vo_en_wpu_en V
OUT_EN
pin charge-pumped, current-limited pull-up enable.
0: Disable weak pull-up. V
OUT_EN
pin driver is three-stated when channel is on.
1: Use weak current-limited pull-up on V
OUT_EN
pin when the channel is on.
b[2] Mfr_config_vo_en_wpd_en V
OUT_EN
pin current-limited pull-down enable.
0: Use a fast N-channel device to pull down V
OUT_EN
pin when the channel is off for any reason.
1: Use weak current-limited pull-down to discharge V
OUT_EN
pin when channel is off due to soft stop by
the CONTROL pin and/or OPERATION command. If the channel is off due to a fault, use the fast pull-down
on the V
OUT_EN
pin.
pMbus coMManD DescripTion