Here is the complete wiring and structural design sketch for a
beginner-friendly, programmable chemistry lab heating and cooling block.
This setup utilizes an Arduino Uno or an ESP32 microcontroller alongside a
heavy-duty IBT-2 H-bridge driver. This setup isolates the high-power 12V DC
lines feeding the Peltier module from the delicate 5V logic running on your
microcontroller.

1. Structural Assembly Layout

Before jumping into the wires, ensure your hardware stack mirrors the
structure below. Even pressure across the entire module face is critical to
prevent hot spots from permanently cracking the micro-junctions inside the
element.
       [ Aluminum Block / Chemistry Vials ]
  ,
 <-- Embedded DS18B20 Temp Probe                         
 <-- Embedded DS18B20 Temp Probe                         
             [ TEC1-12706 Peltier Plate ]
  
         [ Thermal Interface Material (TIM) ]
  
        [ Large Aluminum CPU Heatsink Fin ]
                 [ 12V Cooling Fan ]

2. Electrical Wiring Diagram Sketch

2. Electrical Wiring Diagram Sketch
               12V DC POWER SUPPLY                            
      ,,
 (+12V  (Ground Line)Line)                                  
                  <                            <
                  <                            <
     IBT-               IBT-2       2                
  POWER             POWER INPUT    INPUT             
   (B+              (B- Pin)      Pin)               
                   
                                               
                                               
                                               
     IBT-               IBT-2       2             
  OUTPUT MOTOR+    OUTPUT MOTOR-  6      
    (M+               (M- Pin)     Pin)           
      ,          ,
                                           
               < (Red Wire)                 < (Black Wire)
               < (Red Wire)                 < (Black Wire)
          TEC1-12706 PELTIER MODULE                    
         


         
   ARDUINO /                  IBT-2 LOGIC INPUTS   ESP32        
                                                                
   5V or 3.3V Pin           VCC Pin              6 
   GND Pin            GND Pin              6       
                                                                
   Digital Pin 5 PWM)       RPWM Pin             6
   Digital Pin 6 PWM)       LPWM Pin             6
   Digital Pin 7            R_EN & L_EN Pins     6 
  ,              
               
 (One-Wire Data)              
              <
              <
 DS18B20 TEMP  <-- Needs a 4.7kN) pull-up resistor SENSOR      
 (Data connected      bridged between its Data line to       
  Digital Pin      and its 5V VCC line.2)          
  

3. Logic and Connection Breakdown


Power Side Connections

" The 12V DC power supply directly hooks into the heavy screw terminal inputs
(B+ and B-) on the IBT-2 driver module.
" The Peltier element's leads go straight into the heavy screw terminal
outputs (M+ and M-).

Control Logic Connections

The low-power pin strip on the IBT-2 connects directly to your microcontroller
logic:
" VCC & GND: Powers the integrated isolation chips on the driver board.
" R_EN & L_EN (Right/Left Enable): Tie these two pins together and run them to
a single digital out pin on your microcontroller. Driving this pin HIGH arms
the driver board.
" RPWM & LPWM (Right/Left Pulse Width Modulation): Connect these to
independent PWM-capable pins on your microcontroller.
" Driving RPWM with a variable duty cycle while keeping LPWM at zero pushes
current from M+ to M- (Cooling Mode).
" Driving LPWM with a variable duty cycle while keeping RPWM at zero flips the
current flow from M- to M+ (Heating Mode).
Would you like to examine the basic Arduino code loop layout needed to read
the DS18B20 sensor and route these PWM cooling and heating signals through the
driver board, or do you have everything you need to begin mounting the
hardware?