Datasheet

AD5380 Data Sheet
Rev. C | Page 16 of 40
Mnemonic Function
FIFO EN FIFO Enable (Level Sensitive, Active High). When connected to DVDD, the internal FIFO is enabled, allowing the user
to write to the device at full speed. FIFO is only available in parallel interface mode. The status of the FIFO EN pin is
sampled on power-up, and also following a CLEAR or
RESET
, to determine if the FIFO is enabled. In either serial or I
2
C
interface modes, the FIFO EN pin should be tied low.
DB11/(
SPI
/I
2
C) Multifunction Input Pin. In parallel interface mode, this pin acts as DB11 of the parallel input data-word. In serial
interface mode, this pin acts as serial interface mode select. When serial interface mode is selected (SER/
PAR
= 1)
and this input is low,
SPI
mode is selected. In
SPI
mode, DB12 is the serial clock (SCLK) input and DB13 is the serial
data (DIN) input.
When serial interface mode is selected (SER/
PAR
= 1) and this input is high, I
2
C mode is selected.
In this mode, DB12 is the serial clock (SCL) input, and DB13 is the serial data (SDA) input.
DB12/(SCLK/SCL) Multifunction Input Pin. In parallel interface mode, this pin acts as DB12 of the parallel input data-word. In serial
interface mode, this pin acts as a serial clock input.
Serial Interface Mode. In serial interface mode, data is clocked into the shift register on the falling edge of SCLK.
This operates at clock speeds up to 30 MHz.
I
2
C Mode. In I
2
C mode, this pin performs the SCL function, clocking data into the device. The data transfer rate in
I
2
C mode is compatible with both 100 kHz and 400 kHz operating modes.
DB13/(DIN/SDA) Multifunction Data Input Pin. In parallel interface mode, this pin acts as DB13 of the parallel input data-word.
Serial Interface Mode. In serial interface mode, this pin acts as the serial data input. Data must be valid on the
falling edge of SCLK.
I
2
C Mode. In I
2
C mode, this pin is the serial data pin (SDA) operating as an open-drain input/output.