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WYVERN2742 / Peanut

Pinenut-01S BL602 Motherboard
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Initial Component Selection #3

Open WYVERN2742 opened 2 months ago

WYVERN2742 commented 2 months ago

This is a catch-all issue for the initial component selection. Keep this table up to date:

Type Component Name Manufacturer JLCPCB? Footprints LCSC Cost I2C ADDR Comment
Motion Sensor BNO085 CEVA ❌ ✔ 13.15 0x4A Need to source, somehow...
Humidity & Temperature Sensor HDC2010YPAR Texas Instruments ✔ ✔ $1.04 0x40
Light Sensor LTR-308ALS-01 Lite-On ✔ ✔ $0.44 0x53 (Same as LTR-303ALS-01)
Pressure Sensor LWP040-PSGLC-S Longway ✔ ✔ $0.33 --
8-Channel I2C Digital Muxer PCF8574APWR Texas Instruments ✔ ✔ $0.95 0x38
4-Channel DAC MCP4728T-E/UN Microchip ✔ ✔ $2.24 0x60
Battery Holder (18650) BH-18650-B1BA002 MYOUNG ✔ ✔ $1.13 --
Side-Mounted Tactile Switches XDTD-6643H-L07 Lian Xin Technology ✔ ✔ $0.39 --
Side-mounted Slide Switches SK12D07VG4 SHOU HAN ✔ ✔ $0.02 --
External-Driven Buzzer QMB-09B-03 Jiangsu Huaneng Elec ✔ ✔ $0.57 -- -
3.5mm Audio Jack PJ-320A-4P DIP SHOU HAN ✔ ✔ $0.02 --
LiFePO4 18650 Battery ACL9073B10
(JGCFR18650-1800mAh-3.2v)		 NX - - £70 / 10pcs --
Instrumentation Amplifier INA350ABSIDDFR Texas Instruments ✔ ✔ $0.40 --
4-Channel 16 bit ADC ADS1015IDGSR Texas Instruments ✔ ✔ $1.09 0x48
Transistor MMBT5401 Jiangsu Changjing Electronics Technology ✔ ✔ $0.0129 --
Female JST Connector F185-1204A0BSYA1 Yxcon ❌ ✔ $0.13
Male Pin Header 10129382-908003BLF Amphenol ICC ❌ ❌ £0.14
WYVERN2742 commented 2 months ago

@Brandagot To do sourcing on side-mounted switches @WYVERN2742 To do sourcing on footprints, and compile datasheets

WYVERN2742 commented 2 months ago

Managed to get a working easyeda -> kicad footprint workflow, main limitations are models for strange parts, and some footprints

WYVERN2742 commented 2 months ago

Got datasheets, footprints, and models for all ✔'s in the component table above. Just waiting for buzzer, switch and ADC sourcing

Turns out, the pressure sensor works via a Wheatstone Bridge circuit, so it gives Vout- and Vout+. The differences are too small for direct ADC, so we need to boost them with an opamp before feeding to the ADC.

Not sure if we should feed Vout- and Vout+ seperately into two channels, or compute pressure electronically before ADC to make use of noise removal on the ADC.

WYVERN2742 commented 1 month ago

Added 12-bit ADC ADS1015IDGSR and IntAmp INA350ABSIDDFR for pressure sensing.

Need to collate I2C addresses, and figure out how to wire battery reading;- we may need another i2c muxer for more outs...

Brandagot commented 3 weeks ago

MCP4728T-E/UN, play with LDAC / UDAC settings when we get a dev board. Pulling LDAC low will mean immediate output when sending data.

WYVERN2742 commented 3 weeks ago

Current cost is roughly ~$28.94 / board (or £22.86) without PCB or assembly.

Brandagot commented 3 weeks ago

Need a through-hole right angle push button, instead of surface mount.

WYVERN2742 commented 3 weeks ago

Will bulk-order and manually solder through-hole components, to save on assembly cost

WYVERN2742 commented 3 weeks ago

Added Transistor we're using for battery measurement toggle

WYVERN2742 commented 2 weeks ago

Changed from PCF8574ADWR -> PCF8574APWR (Package change, it's now smaller, in stock and cheaper!)

WYVERN2742 commented 2 weeks ago

Just noticed: We forgot about J1 & J2 Connectors for pinenut and extension boards :/