Other Parts Discussed in Thread: LMX2594
I am programming LMX2572 strictly according to latest datasheet recommendation:
1. Apply power to the device and ensure all the supply pins are at the proper levels.
2. If CE is low, pull it high.
3. Wait 500 μs for the internal LDOs to become stable.
4. Ensure that a valid reference clock is applied to the OSCin pins.
5. Program register R0 with RESET= 1. This will ensure all the registers are reset to their default values.This bit is self-clearing. <--writing 0x219A
6. Program in sequence registers R125,R124,R123,..., R1 and then R0 <--writing 0x2198 to R0.
Register values are exported from TICSPro.
However, I am finding that some parts will never declare lock (R110) after this procedure until R0 is written a second time (0x2198).
Similar part, LMX2594, datasheet requires this second write to R0, and according to other posts in this forum certain parts do not turn on their internal LDOs until first R0 write, thus the need for second write to R0.
TICSPro seems to work because the act of setting and clearing the reset button prior to write registers provides the second R0 write (first one when reset is cleared, second one at end of sequence of register writes).
This seems be part and temperature dependent.
Can you confirm this requirement?
