Sensor modules

AXS-009 — BME280 environment sensor PMOD module

Catalog #9, level L3 (I2C). Combined temperature, humidity, and barometric pressure.

Level L3 ERC clean DRC clean Fab package 9 components

3D render of the AXS-009 PCB — Rendered from the PCB layout. No physical board has been manufactured.

Components#

Every placed component, with the reason it is on the board. Extracted directly from the schematic, so this cannot drift from the design.

Ref	Value	What it does on this board	Part number	Footprint
`C1`	100nF 16V X7R	VDD decoupling	`GRM188R71C104KA01D` Murata	`C_0603_1608Metric`
`C2`	100nF 16V X7R	VDDIO decoupling	`GRM188R71C104KA01D` Murata	`C_0603_1608Metric`
`J1`	PMOD PLUG 2x6	PMOD peripheral plug (Digilent spec 1.2)	not selected generic	`PinHeader_2x06_P2.54mm_Horizontal`
`JP1`	SDA PULL-UP	Cut to remove the SDA pull-up when chaining modules	—	`SolderJumper-2_P1.3mm_Bridged_RoundedPad1.0x1.5mm`
`JP2`	SCL PULL-UP	Cut to remove the SCL pull-up when chaining modules	—	`SolderJumper-2_P1.3mm_Bridged_RoundedPad1.0x1.5mm`
`JP3`	ADDR 0x76/0x77	I2C address select: 1-2 SDO low 0x76 (default), 2-3 SDO high 0x77	—	`SolderJumper-3_P1.3mm_Bridged12_RoundedPad1.0x1.5mm`
`R1`	4.7k	I2C SDA pull-up	`RC0603FR-074K7L` Yageo Datasheet ↗	`R_0603_1608Metric`
`R2`	4.7k	I2C SCL pull-up	`RC0603FR-074K7L` Yageo Datasheet ↗	`R_0603_1608Metric`
`U1`	BME280	Combined temperature, humidity, and pressure sensor	`BME280` Bosch Sensortec Datasheet ↗	`Bosch_LGA-8_2.5x2.5mm_P0.65mm_ClockwisePinNumbering`

Signals#

Net labels used in the schematic, which are also the names the HDL top level should use.

3V3 ADDR GND SCL SCL_PU SDA SDA_PU

Production status#

Schematic ERC	0 violations
PCB layout	complete
DRC	0 violations
Fab package	exported (24 gerbers + drill + CPL + BOM)
Fabricated	no — design stage only

Source: boards/sensor-modules/axs-009-bme280

Catalog #9 (../README.md), level L3 (I2C). Combined temperature, humidity, and barometric pressure.

Status: schematic generated, ERC clean (0/0), netlist reviewed. PCB layout not started. Not released.

What it teaches#

Multi-register I2C reads and fixed-point math: the raw ADC words are useless until combined with the factory calibration coefficients read from NVM — a substantial fabric arithmetic exercise.

Design#

Bosch BME280 (LGA-8), hard-wired for I2C: CSB tied to 3V3.
Address 0x76 with JP3 in the default 1-2 position (SDO low); 2-3 for 0x77.
4.7 kΩ bus pull-ups behind cut jumpers JP1/JP2; 100 nF on VDD and VDDIO.
PMOD Type 6 extended, bus repeated on pins 9/10.

Regenerate / remaining#

python3 generate_design.py — then PCB layout, HDL (i2c_master + compensation pipeline), BOM check, review checklist.