The ADF4110 will start to lock the loop after a write to the AB counter latch.
Your sequence should be something like this:
- Power up ADF4110 and VCO - VCO is output is some frequency between its output limits.
- Program ADF4110 Initialization Latch (see page 20 of the ADF4110 datasheet).
- Program ADF4110 R counter Latch.
- Program ADF4110 AB counter Latch.
- At this point (specifically, the rising-edge of LE on the AB counter Latch SPI write), the loop will begin to lock.
难道, 每次上电后, 都要通过单片机来执行这个序列 ADF4110 才能开始工作?
是否可以烧写之后, 把 LE, CLK, DATA,CE这些引脚 接地(或接VCC, 或悬空), 然后 ADF4110按照之前的设定开始工作 ??