AD5689 datasheet(22/24 Pages) AD

22 / 24 page

AD5689/AD5687

Data Sheet

Rev. B | Page 22 of 24

30B

HARDWARE RESET (

RESETE

)

RESETE

is an active low reset that allows the outputs to be cleared

to either zero scale or midscale. The clear code value is user

selectable via the power-on reset select pin (RSTSEL).

RESETE

must be kept low for a minimum amount of time to complete

the operation (see Figure 2). When the

RESETE

signal is returned

high, the output remains at the cleared value until a new value is

programmed. The outputs cannot be updated with a new value

while the

RESETE

pin is low. There is also a software executable

reset function that resets the DAC to the power-on reset code.

Command 0110 is designated for this software reset function

(see Table 9). Any events on

LDACE

during a power-on reset are

ignored. If the

RESETE

pin is pulled low at power-up, the device

does not initialize correctly until the pin is released.

31B

RESET SELECT PIN (RSTSEL)

The AD5689/AD5687 contain a power-on reset circuit that

controls the output voltage during power-up. When the RSTSEL

pin is connected low (to GND), the output powers up to zero scale.

Note that this is outside the linear region of the DAC. When the

RSTSEL pin is connected high (to VLOGIC), VOUTX powers up to

midscale. The output remains powered up at this level until a

valid write sequence is sent to the DAC.

AD5689 Datasheet(PDF) 22 Page - Analog Devices