LTC3675_12 Datasheet, PDF (30/38 Pages) Linear Technology – 7-Channel Confi gurable High Power PMIC

LTC3675
APPLICATIONS INFORMATION
Choosing the C_T Capacitor
The C_T capacitor may be used to program the timing
parameters associated with the pushbutton. For a given
C_T capacitor the timing parameters may be calculated as
below. C_T is in units of μF.
t_{ONB_LO} = 5000 × C_T ms
t_{PBSTAT_PW} = 5000 × C_T ms
t_{ONB_WAKE} = 40000 × C_T ms
t_{WAKE_ON} = 500 × C_T seconds
t_{ONB_HR} = 500 × C_T seconds
t_HR = 100 × C_T seconds
Programming the UVOT Register
The UV/OT warning byte (default 0000 0000) structure
is as below:
BIT7
RESET_ALL
BIT6
UV[2]
BIT5
UV[1]
BIT4
UV[0]
BIT3
Unused
BIT2
Unused
BIT1
OT[1]
BIT0
OT[0]
Programming the RSTB and IRQB Mask Registers
The RSTB mask register can be programmed by the user
at sub-address 0Ah and its format is as below.
BIT7
Unused
BIT6
BIT5
BIT4
BIT3
BIT2
PGOOD7 PGOOD6 PGOOD5 PGOOD4 PGOOD3
If a bit is set to ‘1,’ then the corresponding regulator’s
PGOOD will pull RSTB low if a PGOOD fault were to occur.
The default for this register is FFh.
The IRQB mask register has the same bit format as the
RSTB mask register. The IRQB mask register is located at
sub-address 0Bh and its default contents are 00h.
PGOOD7 is used only when the LED driver is configured
as a high voltage boost regulator.
BIT1
PGOOD2
BIT0
PGOOD1
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