DEMO09S08DZ60

[laura]

Hi
My name is Laura and I'm having trouble understanding something on the datasheet of my microcontroller. I solved some doubts already but I cannto understand the voltage in the ADC. What pins do I use to specify the range of the voltage to compare or is it fixed? Hope you can help me because this is my first time programming , bye!

[bigmac]

Hello Laura,

For the DZ60 device, external Vref connections are available for the 64-pin package only.  For the smaller packages the connections are internally tied to VddA and VssA, which require to be externally wired to Vdd and Vss, respectively.

For the 64-pin package, the VrefL pin needs to be at the same potential as VssA.  However, the VrefH pin may have an applied voltage between the limits 2.7 volts and VddA.  The reference voltage must not exceed VddA.

However, I do not know whether the demo board configuration makes provision for an externally applied reference voltage.

Regards,

Mac

Message Edited by bigmac on 2008-10-24 11:24 AM

[laura]

Hii
so what you are telling me is that i have to connect voltage to vdd, vss vrfh and vrefl if i have the 64 pin? and vdd can be any voltage and vrefh must be lower than vdd??
another little question...do you know how do i use the buttons and leds and pots that are in the board? im not quite sure how to access them. thanks a lot
lau

[bigmac]

Hello Laura,

Since you are using the demo board, the various power supply connections have already been made - you do not need to make any external connections to the chip.  Note that the ADC reference voltage is already connected to Vdd (refer to the board schematic).  For a different externally applied voltage level, this would required some modifications to the board.

To utilize the various buttons, LEDs and potentiometers, you will need to install "fabricated jumpers" at the appropriate locations on the USER dual row header strip.

Regards,

Mac