I'm trying to output the Vout from the 2nd pin of my AD5791, but I don't succeed to do that.
Could someone give me a hint to solve it?
I don't use the evaluation board for AD5791, and the circuit configuration is almost same as Figure 53. Typical Operating Circuit of the datasheet Rev. D, Page 26 of 28.
I'm using a breadboard to evaluate the AD5791.
VDD = +15 V
VSS = -15 V
VREFPF = VREFPS = +10 V (With AD8676 as shown in Fig. 53)
VREFNF = VREFNS = -10 V (With AD8676 as shown in Fig. 53)
VCC = IOVCC = +5 V
!LDAC = GND
!CLR = !RESET = 3.3 V
Logic Voltage = 3.3 V
10 uF and 0.1 uF decoupling capacitors are connected.
Here I show the sending signals and the output.
Ch1(Yellow) the output of the AD5791. the impedance of the probe is 1 Mohm.
D0 : SCLK (Ch2 Green is also SCLK)
D1 : !SYNK
D2 : SDIN
By above, I set the AD5791 to normal mode, BIN/2sC is BIN, RBUF is 1.
And then, I send bellow pattern, but the output voltage (Ch1, Yellow) doesn't change at all.
I'm using NI USB-7856R to generate above digital signal.
Could someone tell me how can I fix the problem?
And I have one more question.
The datasheet says that "If the RESET pin is not used, it should be hardwired to IOVCC." on page 20.
But in my case, IOVCC is 5 V, and the maximum logic input is limited to 0.7IOVCC (3.5 V in my case) on page 4.
I tried to connect the !RESET pin to 5 V and 3.3 V, but the AD5791 didn't work well both.
Which is correct?
Thank you for your kind help.