HardLabs

SAMPad

mohitg11·SAMPad·PCB/SAMPad.kicad_pcb

SAMPad PCB layout, top view — open source AVR/Arduino board by mohitg11

About the SAMPad PCB

SAMPad is an open source AVR/Arduino PCB design by mohitg11, published on GitHub. It is a 2-layer board measuring 73.2 × 116 mm, with 149 components from 31 distinct parts.

Its main chip is the ATMEGA32U4, from the AVR/Arduino family. Other key parts include the IP4234CZ6 and PAM2804. By type, the board carries 32 switches, 31 LEDs, 24 diodes, 15 capacitors, 9 resistors and 4 connectors.

It belongs with the keyboards designs in this gallery.

From the project

Sundstrand Adding Machine - The modern numeric pad

This is a custom numeric pad that is designed to be usable on the right side of the keyboard or on the left (With a mirrored layout if required). There is a gap in the top row and the second row of 1.25U. The top row can be broken off by simply scoring the two brifges and snapping. The bottom 5 rows can then be used in conjunction with a 60%/65% keyboard.

SAMPad stands for Sundstrand Adding Machine. David Sundstrand was the inventor of the 10-key adding machine, the layout of which is used till date on most numeric pads. This is a humble dedication to the great man.

SAMPad, from the project README
From the project README

Main components on the SAMPad

ATMEGA32U4IP4234CZ6PAM2804

SAMPad bill of materials (BOM)

149 components, 31 distinct parts.

QtyPartRefs
1
ATMEGA32U4
U1
1
IP4234CZ6
U3
1
PAM2804
U5
1
CRYSTAL
X1
2
USB_CONN
P1, P1_2
2
CONN_6
P4, P5
1
BUZZER
BZ1
4
0.1 uF
CLED1, CLED2, CLED3, CLED4
1
PTC FUSE
F1
5
MISC
FID1, FID2, FID3, FID4, HOLE1
1
JUMPER
JP1
4
WS2812B
LEDG1, LEDG2, LEDG3, LEDG4
7
470
RI1, RI2, RI3, RI4, RI5, RI6, RI7
1
TAC_SWITCH
S1
30
SW
S1:1, S1:2, S1:3, S1:4, S2:1, S2:2, S2:3, S2:4 +22
1
ENCODER
S2
6
MISC
STAB1, STAB2, STAB3, STAB4, STAB5, STAB6
30
LED
LED2:2, LED2:3, LED3:1, LED3:2, LED3:3, LED3:4, LED4:1, LED4:1_2 +22
1
LED
LEDI7
24
DIODE
D1:1, D1:2, D1:3, D1:4, D2:1, D2:2, D2:3, D2:4 +16
Show 11 more
QtyPartRefs
1
4.7uH
L2
4
1uF
C1, C2, C22, C23
6
0.1uF
C3, C4, C5, C6, C7, C8
3
10uF
C9, C17, C18
2
8pF
C13, C14
3
10k
R1, R34, R35
2
22
R3, R4
1
100k
R14
1
330
R24
1
RLED
R25
1
100
R33

SAMPad design files

The KiCad project lives in the mohitg11/SAMPad repository on GitHub; these links point at the commit this page was built from.

SAMPad: common questions

What microcontroller does the SAMPad use?

The SAMPad is built around the ATMEGA32U4, from the AVR/Arduino family.

How big is the SAMPad PCB?

The SAMPad measures 73.2 × 116 mm, has 2 copper layers and is 1.6 mm thick.

How many components are on the SAMPad?

149 components, from 31 distinct parts. The full bill of materials is listed on this page.

Where can I download the SAMPad design files?

From the mohitg11/SAMPad repository on GitHub, which has the KiCad layout; the links under Design files point to each one.

Can I use the SAMPad design in my own project?

The repository has no license, so all rights stay with mohitg11. Use it as a reference, and ask the author before reusing the design.

Can I test firmware for the SAMPad without the hardware?

Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug AVR/Arduino firmware against it before you order a PCB.

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