AD5370 datasheet(17/24 Pages) AD

17 / 24 page

Preliminary Technical Data

AD5370

Rev. P

rF | Page 17 of 24

TOGGLE MODE

The AD5370 has two X2 registers per channel, X2A and X2B,

which can be used to switch the DAC output between two levels

with ease. This approach greatly reduces the overhead required

by a micro-processor which would otherwise have to write to

each channel individually. When the user writes to either the

X1A ,X2A, M or C registers the calculation engine will take a

certain amount of time to calculate the appropriate X2A or X2B

values. If the application only requires that the DAC output

switch between two levels, such as a data generator, any method

which reduces the amount of calculation time encountered is

advantageous. For the data generator example the user need

only set the high and low levels for each channel once, by

writing to the X1A and X1B registers. The values of X2A and

X2B will be calculated and stored in their respective registers.

The calculation delay therefore only happens during the setup

phase, i.e. when programming the initial values. To toggle a

DAC output between the two levels it is only required to write

to the relevant A/B Select Register to set the MUX2 register bit.

Furthermore, since there are 8 MUX2 control bits per register it

is possible to update eight channels with a single write. Table 14

shows the bits that correspond to each DAC output.

AD5370 Datasheet(PDF) 17 Page - Analog Devices