Rainbow Electronics MAX1386 - Manual (Page 52)

MAX1385/MAX1386
Dual RF LDMOS Bias Controllers
with I
2 C/SPI Interface
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Appendix: Recommended
Power-Up Code Sequence
The following section shows the recommended startup
code for the MAX1385. This code ensures clean startup
of the part, irrespective of power-supply ramp speed
and starts the device regulating to 312.5mV on both
channels. Change the THRUDAC writes to change the
voltage across the sense resistor. Note it should be run
after the power supplies have stabilized.
*Double reset. This ensures that the internal ROM is reset correctly after power-up and that the ROM data is latched correctly irre-
spective of power-supply ramp speed.
REGISTER
MNEMONIC
REGISTER
ADDRESS (hex)
CODE
WRITTEN
NOTES
SHUT 0x64 0x0080 Removes the global power.
SHUT 0x64 0x0080
Powers up all parts of the MAX1385 and forces the internal reference to
remain powered. The internal oscillator is required for the subsequent
reset command.
SCLR 0x68 0x0100 Arms the full reset.
SCLR 0x68 0x0200 Completes the full reset.
SCLR 0x68 0x0100 Arms the full reset.*
SCLR 0x68 0x0200 Completes the full reset.*
SHUT 0x64 0x0080 Removes the global power.
SHUT 0x64 0x0080
Powers up all parts of the MAX1385 and forces the internal reference to
remain powered. The internal oscillator is required for the subsequent
reset command.
DCFIG 0x30 0x000A Selects internal references for both DAC and ADC.
PGACAL 0x4E 0x0002
Runs autocalibration on both PGA channels to set the input referred
offset to < 50µV. Busy goes low after approximately 30ms and then the
V
GATE DACs can be set.