MAX1385 Datasheet, PDF (48/52 Pages) Maxim Integrated Products – Dual RF LDMOS Bias Controllers with I2C/SPI Interface

Dual RF LDMOS Bias Controllers
with I²C/SPI Interface
Table 28. DAC Write Commands Without Autocalibration
ACTION REQUIRED
RECOMMENDED COMMAND SEQUENCE
OTHER POSSIBLE COMMAND
SEQUENCES
Update fine DAC_ without triggering
autocalibration.
Write to FINE_. Write to LDAC to update fine Write to FINETHRU_ to immediately
DAC_.
update fine DAC_.
Update high wiper coarse DAC_ without
triggering autocalibration.
Write to HIWIPE_ with HCAL set to 0. Write Write to THRUHI_ to immediately
to LDAC to update high wiper coarse DAC_. update high wiper coarse DAC_.
Update low wiper coarse DAC_ without
triggering autocalibration.
Write to LOWIPE_ with LCAL set to 0. Write Write to THRULO_ to immediately
to LDAC to update low wiper coarse DAC_. update low wiper coarse DAC_.
Immediately update fine DAC_ without
triggering autocalibration.
Write to FINETHRU_.
None.
Immediately update high wiper coarse
DAC_ without triggering autocalibration.
Write to THRUHI_.
None.
Immediately update low wiper coarse
DAC_ without triggering autocalibration.
Write to THRULO_.
None.
Update the high, low, and fine components
of DAC_ simultaneously without triggering
Write to HIWIPE_, LOWIPE, and FINE_.
autocalibration.
Write to LDAC to update DAC_.
None.
1111 1111 1111
1111 1111 1110
1111 1111 1101
1111 1111 1100
V_REFADC
FULL-SCALE TRANSITION
1 LSB = ^VREFADC
4096
0111 1111 1111
0111 1111 1110
0111 1111 1101
0000 0000 0001
0000 0000 0000
1111 1111 1111
1 LSB = +0.125°C
0000 0000 0011
0000 0000 0010
0000 0000 0001
0000 0000 0000
0123
4093 4095
INPUT VOLTAGE (LSB)
Figure 25. ADC Transfer Function
1000 0000 0010
1000 0000 0001
1000 0000 0000
-256°C
0°C
TEMPERATURE (°C)
Figure 26. Temperature Transfer Function
+255.875°C
limits are within the safe operating area. Configure the
ADC for continuous conversions to allow continuous
measurement and testing against configured alarm
thresholds. Connect SAFE_ to OPSAFE_ to immediately
force the gate drive to GATEGND in the event of an
alarm-related condition (current or temperature).
Triggering DAC Calibration
Performing the autocalibration routines requires use of
the internal ADC, the internal ALU, and can also
increase the power dissipation of the part. Tables 28
and 29 detail which commands trigger autocalibration
and which commands do not.
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