Dear fellows,
We need to design a simple regulator using TLC5602 (to control the voltage) + opa564 (to provide the current source).
For the moment, we just need to realize the opa564 as a simple non-inverting unity gain.
The output is connected directly to the Vin- (Rf ~0) and I left the Vin- unconnected to the ground (R1 ~ >>>). So the Av = (Rf+R1)/R1 ~ 1.
I put the 47Kohm for Iset resistor, and set the decoupling capacitor to be 0.1uF (ceramic) and 47uF (tantalum) as recommended for both Vanalog line.
V+ and V+PWR = 7.0V, V- and V-PWR = 0Vm Vdig=5.0V, and the Vanalog is powered after Vdig to the device as recommended.
The E/S is unconnected, and I did not put the Rload.
When I connected the power supply to the device, I found the there was a DC 5.0V at the Vin+ (I left the Vin+ floating) and a DC 5.xxV at the output.
I think if I left the Vin+ floating (unconnected), there should not be any voltage at this pin. CMIIW.
I tried to reconnect the device on the breadboard and still got the same issue.
Any helps would be appreciated.
Thank you in advance.
Regards,
Richard Prasojo
