Re: Current consumption
|
There have been two major component changes in the QDX over the course of its availability that may affect its power consumption. The first is the synthesizer chip. Version 1 used the Si5351A from Silicon Labs. Versions 2 and 3 use the MS5351M from Hangzhou Ruminang Tech, due to unavailability?of the SiLabs (now Skyworks) parts. According to a report, the MS5351M uses about 8mA more current than the Si5351A. Hans Summers reports that the MS5351M has slightly better phase noise performance. The other is the audio codec. A different one is used in Version 3 because the one used in the previous versions was discontinued. One other switch may have decreased current consumption slightly in versions 2 and 3. Version 1 had pullup resistors on some open collector outputs. In versions 2 and 3, those resistors are removed; instead, the firmware activates the on-chip pullups. Loading newer firmware on a version 1 board may increase power consumption a tad because both sets of pullups are active, though you can remove the unneeded resistors from the board if you want. On Fri, Aug 12, 2022 at 10:52 AM Don DeGregori <ddegreg1@...> wrote: I believe the early version of QDX used a different chip. When it became unavailable |
Shirley Dulcey KE1L