AD Keypad
  •  AD Keypad
  •  AD Keypad
  •  AD Keypad

AD Keypad

:LCD02003
€4.02
Tax included
Quantity

If you have any questions on this product please feel free to contact us.

*Disclaimer: The images are merely illustrative.

 

Overview

The AD Keypad provides 16 push buttons, and takes up only 1 AD port for controlling. It's suitable for applications where the AD ports are sufficient yet I/O ports are lacking of.

 

Features

16 push buttons, detection interface

 

Photos

 

Parameters and How to

Parameters and Sampling

  • AD ideal value: when button pressed, Viv = (button index / 16) x Vref
    AD real value: when button pressed, Vrv = (1 ± 6%) x Viv
    For instance, suppose Vref = 5, 8th button was pressed, then Viv = (8 / 16) x 5 = 2.5, Vrv = (1 ± 6%) x 2.5, equals to 2.35-2.65
  • Abbreviation
    • Vref: AD reference voltage
    • iv: ideal value
    • rv: real value

 

ADC Value Detection Range

Measurement Data (Vref=3.3V)

Measurement Data (Vref = 5V)

Buttons

10-bit ADC

8-bit ADC

Real Value 
Sampling (V)

Error (V)

Ideal Value (V)

Real Value 
Sampling (V)

Error (V)

Ideal Value(V)

0

0-4

0-1

0

0

0

0

0

0

1

(1±6%)x64

(1±6%)x16

0.2054

-0.00085

0.20625

0.3112

-0.0013

0.3125

2

(1±6%)x128

(1±6%)x32

0.4117

-0.0008

0.4125

0.6238

-0.0012

0.625

3

(1±6%)x192

(1±6%)x48

0.6233

0.00455

0.61875

0.9444

0.0069

0.9375

4

(1±6%)x256

(1±6%)x64

0.8242

-0.0008

0.825

1.2487

-0.0013

1.25

5

(1±6%)x320

(1±6%)x80

1.0304

-0.00085

1.03125

1.5612

-0.0013

1.5625

6

(1±6%)x384

(1±6%)x96

1.2355

-0.002

1.2375

1.8719

-0.0031

1.875

7

(1±6%)x448

(1±6%)x112

1.4448

0.00105

1.44375

2.189

0.0015

2.1875

8

(1±6%)x512

(1±6%)x128

1.6541

0.0041

1.65

2.5061

0.0061

2.5

9

(1±6%)x576

(1±6%)x144

1.8637

0.00745

1.85625

2.8237

0.0112

2.8125

10

(1±6%)x640

(1±6%)x160

2.0732

0.0107

2.0625

3.1411

0.0161

3.125

11

(1±6%)x704

(1±6%)x176

2.2672

-0.00155

2.26875

3.435

-0.0025

3.4375

12

(1±6%)x768

(1±6%)x192

2.4712

-0.0038

2.475

3.7441

-0.0059

3.75

13

(1±6%)x832

(1±6%)x208

2.6789

-0.00235

2.68125

4.0588

-0.0037

4.0625

14

(1±6%)x896

(1±6%)x224

2.8902

0.0027

2.8875

4.3789

0.0039

4.375

15

(1±6%)x960

(1±6%)x240

3.1092

0.01545

3.09375

4.7107

0.0232

4.6875

 

How to detect and handle in your code

For 10-bit ADC, the 8th button generates ADC value between (1±6%)x512, the equivalence of "481-543". If the ADC value had been detected to be "510-518" in the code, the 8th button's supposed to have been pressed.

For 8-bit ADC, the 8th button generates ADC value between (1±6%)x128, the equivalence of "120-136". If the ADC value had been detected to be "124-128" in the code, the 8th button's supposed to have been pressed.

 


Downloads

Development resources: demo codes, schematic, datasheets, etc.
Wiki: www.waveshare.com/wiki/AD_Keypad

LCD02003

You might also like