DT830B Inside View

The design and construction of the DT830B is interesting. Based around a single chip digital meter solution, there is one Chip on Board (COB) package.

The construction is very neat, with accurate soldering. The surface-mount device (SMD) placement is accurate and appears to be machine manufactured requiring minimal manual labour.

Using SMD reduces the manufacturing cost and allows manufacturers to build smaller products. I like this well manufactured Printed Circuit Board (PCB). I have many projects I would love to make, but cannot even get one PCB etched because the price here in the UK is very high.

COB Packages

Mounted directly on the PCB, there are only one or two firms in China capable of making this type of IC. This is very likely an ICL7106 or a variant of it. A single chip solution like this lowers the cost of manufacturing drastically. The Analogue to Digital Converter (ADC), LCD driver, including the software, is all in this one chip.

Meters made with this type of chip will generally exhibit similar accuracy figures because the ADC circuitry is always the same.

PCB Marking

The marking on the PCB indicates 830B Version 4C. According to the manual, the 830C model has an audible buzzer for continuity testing, and there are pads on this PCB for such a buzzer. I wonder if it would work if I connected a buzzer to it.

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