Low Component Cost Single Tube Induction Cooker
WAS-2041EN V1.00
7 / 19
February 25, 2021
Layout and Hardware Considerations
There are some important considerations for the power heating board.
1.
The filter capacitors next to the MCU should be located as close to VDD and VSS as possible
and the ground of the peripheral circuit should be a single point grounded to the source capacitor
ground. The resonance circuit ground should be separated from other peripherals to avoid the
IGBT switching interference signal influencing other peripherals. Also ensure that the routes go
through a voltage regulation filtering capacitor to filter out any noise.
2.
Routes from the bridge rectifier to resonance circuit should be widened as these routes carry
larger currents. The resonance capacitor should be as close as possible to the induction cooker
resonance coil.
3.
Routing which is close to the high power area and the low power zone should be separated via
the KEEPOUT layer.
4.
The IGBT E pin and the ground of the bridge rectifier IC should be widened and a single point
connected via a constantan wire, which is then single point routed to the current detection circuit.
Figure 7. Power Heating Board PCB
There are some considerations for the Touch MCU BS86D12C on the touch & display board.
1.
The filter capacitors next to the MCU should be located as close to VDD and VSS as possible.
2.
When there are multiple touch keys on the PCB, the MCU should be located to the center position
among these touch keys, thus shortening the route to reduce any effects of interference. Using
capacitors between the MCU corresponding KEY pins and VSS is an effective method of adjusting
the touch sensitivity. Wires can be routed from the MCU to the KEY pins on the copper floor to
reduce any interference on the touch keys caused by signal wires. It should be noted that any touch
key routing should be located as far as possible from the high frequency signal paths.
Figure 8. Touch & Display Board PCB
