User guide

Si471x-EVB
Preliminary Rev. 0.4 7
Fixed +3.3V
Only one LDO is being used in this mode which outputs a +3.3 V supply to all three Vdd, Vio, and Vmcu supplies.
The jumpers need to be set according to Figure 6. This is the default configuration of the EVB.
Figure 6. Default Fixed +3.3 V Jumpers Setting
Adjustable Vdd and Vio
In case Vdd and Vio supplies to the Si471x chip need to be adjusted or swept, two adjustable LDOs have been put
on the EVB. The Vio supply can be adjusted via potentiometer R73, while Vdd supply via R74. The jumpers need
to be set according to Figure 7.
Figure 7. Adjustable Vdd and Vio Jumpers Setting
Terminal Block Power Supply
If the terminal block supplies are used, then jumpers J61, J68 and J69 need to be set to TB according to Figure 8.
The user then needs to connect three different power supplies, one each for Vdd, Vio and Vmcu.
Figure 8. Terminal Block Jumpers Setting
J69J68
J61
ADJ
+3.3V
TB
ADJ
+3.3V
TB
+3.3V
TB
Vio Vdd Vmcu
J69
J68
J61
ADJ
+3.3V
TB
ADJ
+3.3V
TB
+3.3V
TB
Vio Vdd Vmcu
ADJ
+3.3V
TB
+3.3V
TB
ADJ
+3.3V
TB
J69
J68 J61
Vio Vdd Vmcu