digitaal/analoog converter

digitaal/analoog converter

A PCF8591 AD / DA chip introduced 
    PCF8591 is a monolithic , single supply, low power ,8-bit CMOS data acquisition device . PCF8591 has four analog inputs, one analog output and a serial I2C bus interface . PCF8591 the three address pins A0, A1 and A2 can be used for programming the hardware address , allowing access to the same I2C- bus PCF8591 8 devices without the need for additional hardware. PCF8591 device on the input and output address, control and data signals are bi-directional two-wire I2C-bus for transmission in a serial manner . 
 
PCF8591 key performance indicators: 

•   single power supply 
•   PCF8591 operating voltage range of 2.5V-6V 
•   Low Standby Current 
•   via I2C -bus serial input / output 
•   PCF8591 through 3 hardware address pins addressing 
•   PCF8591 I2C bus speed sampling rate decision 
•   4 analog inputs programmable as single-ended or differential inputs 
•   auto increment channel selection 
•   PCF8591 analog voltage range from VSS to VDD 
•   PCF8591 built-in track and hold circuit 
•   8-bit successive approximation A / D converter 
•  Through an analog output of the DAC gain 

  
Two baby description 

•  A module chip PCF8951 
•  2 module supports an external 4-channel voltage input capture ( voltage input range 0-5v) 
•  3 module integration photoresistor , you can capture the ambient light intensity through the AD precise values 
•  4 module integrated thermistor temperature by exact numerical AD acquisition 
•  5 module integrates a channel 0-5V voltage input capture ( via the blue potentiometer adjustment input voltage ) 
•  6 module with power indicator ( the module after power indicator lights ) 
•  7 module with DA output indicator , when the module DA output interface voltage reaches a certain value , the board will be lit DA output indicator, the higher the voltage , the light intensity is more obvious ; 
•  8 Module PCB size : 3.6cm * 2.3cm 
•  9 standard double panel , thickness 1.6mm, nice layout , surrounded by a through hole , aperture : 3mm, convenient fixed 

  
Three module interface description 
This module expansion outside the left and right , respectively, 2-way pin header , respectively, as follows: 
  DA output interface chip left AOUT 
       AINO chip analog inputs 0 
       AIN1 chip analog inputs 1 
       AIN2 chip analog inputs 2 
       AIN3 chip analog input interface 3 
  Right SCL IIC clock interface connected microcontroller IO port 
       SDA IIC digital interface connected microcontroller IO port 
       GND Module to external ground 
       VCC Power Interface External 3.3v-5v 
  
Four modules use red short cap 
  There are three red module shorted cap, respectively function as follows : 

•   Connect the shorting cap P4 P4 , select thermistor access circuit 
•   Connect the shorting cap P5 P5 , select photoresistor access circuit 
•   Connect the shorting cap P6 P6 , select 0-5V Adjustable voltage access circuit