Question
A. SER/PAR' pin should it be connected to DGND?
B. Where should I connect REF_GND and REFOUT/REFIN pins?
C. FIFO_EN pin should it be connected to DGND?
D. Where should I connect MON_OUT & mON_IN (1-4) pins?
E. Where should I connect SDOUT/(A'/B) pin?
Answer
[A] SER/PAR' should be grounded for parallel operation.
[B] REF_GND is an analog ground pin and should go to your analog ground via a
short, low resistance, interference-free connection (i.e. no long or thin
tracks, no "isolating" resistance or inductance). If you are using the internal
reference REFOUT/REFIN should be left open circuit (or connected to any
external [HIGH IMPEDANCE!] circuitry which is using the same reference), if you
are using an external reference it should be connected to this pin. Note that
the choice of reference is programmed by the user.
[C] If you are not using the FIFO then FIFO_EN should be grounded. In theory it
should go to DGND, but if it makes your layout more simple there is probably no
reason why you should not connect it to AGND.
[D] Read the "Pin Function Descriptions" (Pages 9-11 of the Preliminary Data
Sheet) for a description of these functions. If you are not using MON_OUT leave
it open-circuit, if you are not using some or all of the MON_IN inputs ground
them to AGND.
[E] In parallel mode leave SDOUT open-circuit.