Brymen BM857
The Brymen BM857 is a 50000 counts (500000 DC), CAT IV handheld digital multimeter with infrared connectivity.
Hardware
Multimeter:
- Multimeter IC: TBD
- Precision +2.5V Voltage reference: Analog Devices REF43
- True RMS-to-DC converter: Analog Devices AD737
- EEPROM(?): Chip marked S24C0.
- Unidentified: Several 062-JRC chips. These appear to be JFET opamps.
- Unidentified: Two QFP64 chips.
- TODO
Cable:
- TODO
See http://sigrok.org/wiki/User_talk:Mrnuke#BM857_PC_Interface_cable
Photos
Multimeter:
Box
Mughsot
Device, back
Package contents
Probe cable storage clips
Holster removed, front
Holster removed, back
Case opened
Rear cover
Front cover
Rear cover, PCB removed
Upper PCB, top
Upper PCB, bottom
Main PCB, top
Main PCB, bottom
High voltage isolation slots.
High voltage isolation walls, designed to fit in the isolation slots.
Input circuit near the V jack
Microcontroller (right), and LCD controller (left)
Microcontroller (right), and LCD controller (left)
LCD controller and connector
ICs on the main PCB
More ICs
Cable:
We don't have a cable (BC-85Xa) for this device. Currently, mrnuke is working on an improvised USB-to-infrared converter for development purposes. If you have a BC-85Xa you'd like to donate, contact mrnuke on #sigrok.
Protocol
TODO
Resources
TODO