HardLabs

Filter Board

frohro·pico-dev-ice·Hardware/Filter_Board/Filter_Board.kicad_pcb

Filter Board layout, top view — open source board by frohro

About the Filter Board

Filter Board is an open source PCB design by frohro, published on GitHub. It is a 2-layer board measuring 33 × 33 mm, with 20 components from 8 distinct parts.

By type, the board carries 9 jumpers, 4 capacitors, 3 connectors, 3 inductors and 1 resistor.

It belongs with the rf & radio and audio designs in this gallery.

From the project

This is a direct down conversion (DDC) HF transceiver & VNA using the Raspberry Pi Pico and the iCE40UP5K.

Designed specifically as an educational platform, it abandons "black box" RF chips in favor of discrete, observable analog blocks. Students can physically probe the RF signal path, design their own LC filters on pluggable sandboxes, and write Verilog to perform Digital Down Conversion (DDC), digital decimation, and hardware I2S audio routing.

Level Shifters (Logic Inversion): The 4.5V analog switches are controlled by 3.3V GPIOs via 2N7002 N-Channel MOSFETs. Note: This results in a logic inversion. Writing 0 to the pin = Switch HIGH (Max Gain / Default Path). Writing 1 = Switch LOW…

Filter Board, from the project README
From the project README

Filter Board bill of materials (BOM)

20 components, 8 distinct parts.

QtyPartRefs
1
PCB Connector
J1
1
IN
J14
1
OUT
J15
5
Jumper_2_Bridged
JP1, JP2, JP6, JP7, JP8
4
Jumper_2_Open
JP3, JP4, JP5, JP10
3
L_Iron_Small
L1, L2, L3
4
C_Small_US
C6, C7, C8, C9
1
50
R1

Filter Board design files

The KiCad project lives in the frohro/pico-dev-ice repository on GitHub; these links point at the commit this page was built from.

Filter Board: common questions

How big is the Filter Board?

The Filter Board measures 33 × 33 mm, has 2 copper layers and is 1.6 mm thick.

How many components are on the Filter Board?

20 components, from 8 distinct parts. The full bill of materials is listed on this page.

Where can I download the Filter Board design files?

From the frohro/pico-dev-ice repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.

Can I use the Filter Board design in my own project?

The repository has no license, so all rights stay with frohro. Use it as a reference, and ask the author before reusing the design.

More boards in pico-dev-ice

Similar boards