AN4536 Application Note Rev. 2.0 1/2014
20
Freescale Semiconductor
OTP Overview
Often only bits 1, 2, and 3 need to be set, as well as the START bit, to reload the TBBOTP registers after the fuses
are programmed. The TBBOTP register values could then be checked to make sure the correct values have been
loaded from the fuses. Setting bits 4 and 5, updates the regulator parameters immediately. This should be done with
caution if PWRON is already asserted. A PWRON event triggers a complete reload using the same logic. When a
'1' is written to Bit 7 of the OTP_LOAD_MASK registers, the MMPF0100 is turned off momentarily and then turned
back on to reload the fuses. If it is desired to reload the fuses without first turning off the MMPF0100, clear Bit 0 of
the PWRCTRL_OTP_CTRL register prior to writing to the OTP_LOAD_MASK register. Note that the
OTP_LOAD_MASK is register 0x84 in Extended Page 1 whereas the PWRCTRL_OTP_CTRL is register 0x88 in
Extended Page 2.
Table 30. OTP Reload Mask Register Bit Description
Bit
Name
Description
0
RSVD
Reserved
1
RL_OTP_FUSE
Reload the OTP fuse latch from the analog fuse bit
0 = Disable loading
1 = Enable loading
2
RL_OTP_ECC
Reload the OTP ECC registers. Set this bit irrespective of whether ECC is
enabled or disabled.
0 = Disable loading
1 = Enable loading
3
RL_OTP
Reload the TBBOTP registers from the fuses
0 = Disable loading
1 = Enable loading of fuses if ECC is disabled. Enable loading of ECC corrected
fuses if ECC is enabled.
4
RL_PWRCTL
Reload the power control registers from the TBBOTP registers
0 = Disable loading
1 = Enable loading
5
FORCE_PWRCTL
Forces the power control registers to be reloaded if they are being used to control
the regulators
0 = No reload forced
1 = Power control register value affects regulators when the reload sequence is
enabled and RL PWRCTL bit is enabled.This is needed when changing output
voltage of switching regulators from low-voltage range to high-voltage range
6
RL_PWRTN
Reloads the register that controls how the PWRON button works
0 = PWRON configuration setting does not change until a shutdown and restart
event
1 = PWRON behavior switch to new OTP PWRON button configuration when
START bit is enabled
7
START
Reload sequence start bit
0 = Reload sequence disabled
1 = Starts the reload sequence, when the sequence is done all of the
OTP_LOAD_MASK bits are reset