CS/A65 Power supply
This board implements the basic power supply facilities, using a standard PC power supply as actual supply. It has a 3.3V power generation, a 50Hz signal, as well as battery backup (incl. Li-ion battery charging circuit
Additionally it includes a Reset circuit and a 16MHz clock source, as well as (since 1.1) an I2C realtime clock and flash ROM.
The 3.3V generation uses a standard LM317 voltage generator. The 50Hz generation uses the CMOS (this is important) version of the LMC555. Both schematics come from www.elektronik-compendium.de.
The Li-ion battery charger is a standard schematics from the datasheet of the used MAX712 battery charger.
Table of content
Board revisions
Version: 1.1B
Status: prototype
Notes
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This board has all features. It fixes the bugs in the 1.1A version: no /RESET pullup, wrong R17 value for the 3.3V generation, and decoupling capacitors for the I2C ICs. Also it has the addresses of the I2C chips fixed (in V1.1A they have the same I2C address...) |
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The layout is untested. |
Files
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csa_pwr-v1.1b.sch |
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csa_pwr_v1.1b-sch.png |
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csa_pwr-v1.1b.brd |
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csa_pwr_v1.1b-brd.png |
Version: 1.1A
Status: prototype with bugs
Notes
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Watch out, this board has a wrong resistor R17 value and other bugs, see description of 1.1B. |
Files
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csa_pwr-v1.1a.sch |
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csa_pwr_v1.1a-sch.png |
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csa_pwr-v1.1a.brd |
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csa_pwr_v1.1a-brd.png |
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csa_pwr_v1.1a.png(Without the battery, though) |
