39 lines
1.3 KiB
Plaintext
39 lines
1.3 KiB
Plaintext
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Name
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1. Question text:
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CO sensor
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2. Design summary:
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Very well written. Low Battery detection / alert is especially well done
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3. Block diagram
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Where is the block diagram?
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you have given the entire electrical circuit diagram here.
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Only some logical / hierarchical block diagram was needed here.
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4. Power supply design
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There are two major probems with your design.
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a. The 9V battery you have chosen is not exactly good for long life. Look at other products that need long life batteries -
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all use some kind of non-rechargeable lithium cells.
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b. You are using a linear regulator which has expremely poor efficiency - you're going from 9V to 5V!
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Should have used a 6V battery and LDO.
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Microcontroller - pick one with low power consumption and/or sleep modes like the MSP430 or AtTiny.
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5. Industrial Design:
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Summary is fine - should have included sketches of the final unit. Where should the LED be? Where are the mountings for
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buzzer / speaker?
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6. KICAD Design
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Schematic:
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No major issues seen
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PCB:
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Layout could be a little better - you have many traces intersecting / overlapping.
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Especially look at the sensor heater supply - those traces could be thicker.
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What is the current needed there?
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7. Pricing / BOM / Assembly
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Some BOM optimisation could have been done - mostly all ok
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Price for 2 prototypes not mentiones?
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