Problem about the schematic circuit of DA14580

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zhehanc
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Problem about the schematic circuit of DA14580

For the buck working mode, we find the Figure 69: Lithium Coin Cell Powered System Diagram (Buck Mode) in datasheet page219.

For the circuit, I have a euqation that why we need to use an inductor L1 at swich pin. Because I think with the decoupling capacitor, we already can remove the high frequency noise

Device: 
PM_Dialog
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Hi zhehanc,

Hi zhehanc,

DA14580 can be configured without the DCDC converter and without the L1 inductor. In this case the efficiency is worse hence the current out of the battery is higher. If you would like to save the cost of the inductor and power consumption is no issue, then the bypass mode (no DCDC) can be used

Thanks, PM_Dialog

PM_Dialog
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Last seen: 11 min 31 sec ago
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Joined: 2018-02-08 11:03
Hi zhehanc,

Hi zhehanc,

If you would like to implement bypass mode on DA14580 (run without DCDC converter and inductor), you should proceed with the following modifications:

  • connect VBAT = VBATRF = VDCDC = VDCDC_RF directly to 3V coin-cell battery.
  • connect “switch” to a high voltage via a resistor 100k (or 1M, not critical) to VBAT (or to VDCDC, no preference)

Thanks, PM_Dialog