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Topic: Minimum setup adns 9500 aka trying to read the sensor block diagram (Read 1 time) previous topic - next topic

Dungeon

Hi!

I want to get the ADNS 9500 (Datasheet) with the Arduino UNO to work. (via SPI)

Therefore I'm trying to figure a "minimum setup" out. For starters I just want to read the delta values and the motion pin.

Currently I have the following pins (numbers from adns datasheet) connected:

SPI: 3,4,5,6 --> SPI Pins on Arduino
Motion: 7 --> some digital input pin on Arduino
VDD5: 9 --> 5 Volt Supply
PWR_OPT: 10 --> Ground
Ground: 11 --> Ground
DGround: 14 --> Ground
VDDIO: 15 --> 3.3V

With this Setup I can flash the firmware and read the version/revision numbers, but the rest of the output remains garbage. I guess the missing pins are the problem.

Unfortunately I'm not really good at reading or interpreting the sensor block diagram. So I have a few questions:

1. Can I use a normal ground pin on Arduino as digital ground?

2. For the pins 1,2,8,16 I need a capacitor and a pMosfet. (top middle of the diagram). But there are some strange things for me:
a. Is the diode connecting the source and drain really necessary? And if, what is it for?
b. Is the resistor on the left necessary? And if, how do I know which one? The datasheet says nothing regarding this.
c. Are those 2 (diode like looking) things above Schottky-diodes? And if, what the hell? Two diodes serial in different directions should do nothing, or am I wrong?
Or do all those elements belong to the pMosfet and are (sort of integrated)? In this case I wouldn't need to worry about this.
d. When I search for NTA4151P I find a pMosfet with 3 pins. On the eye safety diagram it looks like I need 4 pins. On the other hand I read that, two of the 4 pins (bulk and source), are connected internal anyway. So I guess a 3 pin pMosfet is enough?

3. On the diagram I see 5 times almost the same: Some sort of loop including a capacitor and a polarized capacitor, leading to (digital) ground. (loop.png) Those do not look that important to me. Are they for smoothing the power output?

4. What is VDD1, VDD2 and VCC1? The datasheet explains VDD3 and VDD5. Also those (power supplies?) are directly connected to ground - through the loop described in 3. This is important because atm the Pins 9 and 15 (VDD5 and VDDIO) are connected to 5V and 3,3V.

5. I think this question is connected to 4, but what is this? (rings.png)

Help would be appreciated.
Thanks in advance!

Dungeon

#1
Sep 17, 2014, 11:15 am Last Edit: Sep 17, 2014, 11:17 am by Dungeon Reason: 1
Ok
Some of the questions got solved.

2: All blue parts in that area belong to the mosfet. --> no aditional parts needed

3: The Capacitors are important for smoothing the power Output.

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The remaining (and rephrased) questions are:
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1: Can I use GND as digital GND?

2: In the datasheet VDD1 and VDD2 are not defined. Only VDD3 and VDD5. So what am I supposed to use as power supply for the mosfet?
The eye safety diagram says VDD3 which is ~3V. This would indicate that VDD2 and VDD3 are the same.
This would leave VDD1 as VDD5 (~5V). Could this be correct?
Why would I have a choice in the 5V Mode between different sources? I assume the rings and lines near to VDD1/VDD2 represent switches and therefore a choice.

Also: What's the insulated part in the top left corner?

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