0x0D: 32 ch Taguchi array heater switcher




Please see the e-nose project page for an elaborate description as well as practical examples.


This PCB allows each heater voltage VH for a 32 ch Taguchi gas sensor array to be controlled individually. Heaters can either be turned on and off via jumpers or be controlled over the I2C bus via the MCP23017 GPIO port expander.

License terms
The 0x0D design is published under the Creative Commons Unported 3.0 License.  I do not profit from this design, neither should you. You are welcome to adapt, modify, and redistribute this design as long as the license terms are respected.

Physical size of PCB

100 mm (width) by 50 mm (height). Double-sided.

Rendering and photos

0x0D_rendering_front DipTrace 3D rendering

0x0D_backPhoto of the PCB backside

0x0D_16ch_assembledPhoto of the PCB frontside, 16 ch


Photo of the PCB frontside, 32 ch

Bill of materials

16 (32) pcs. resistors, 390R, form factor 1206 (SMD)

16 (32) pcs. LED,  form factor 1206 (SMD)

1 (2) pcs. MCP23017 port expander (SMD)

3 (6) pcs. 100 nF ceramic capacitor, form factor 1206 (SMD)

2 (4) pcs. ULN2803LW eight channel Darlington array (SMD)

1(2) pcs. 48 pin (3 rows each 16 pins) male header, 2.54 mm pitch

1(2) pcs. 9 pin (3 rows each 3 pins) male header, 2.54 mm pitch

19 (38) pcs. jumper, 2.54 mm pitch

1 pcs. 80-pin (2 rows each 40 pins) 2.00 mm pitch male header, angled 90°

1 pcs. DS2401Z

Estimated cost

Sixteen resistors and LEDs, two ULN2803LW, one MCP23017, headers, and jumpers should not cost more than EUR 10,- (16 ch).


Schematic PDF: 0x0D_schematic

DipTrace v. 2.4 schematic file: 0x0D_schematic

DipTrace v. 2.4 PCB design file: 0x0D_ratlined

Gerber files: 0x0D_Gerber


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