What are this components on uBlox EVA M8M GPS?

Question

I am designing my own pcb board based on a Sodaq One V3 (I built my prototype with a Sodaq One V3 and a MAX30102) and I am currently integrating both devices in KiCAD but I have a doubt with the GPS components. The official page says the GPS is an uBlox EVA M8M and I already have the symbol and footprint, but I have doubt with the 1575.42 Mhz SAW filter U3 Component (could I use this one? B39162B9416K610), the schematic GPS circuit schematic is:

And the other doubt is about U4 component, I have no idea what that component is, I also tried to see other Sodaq boards schematics but no success since other boards do not have GPS module. Could somebody help me please?

Answer 1

The EVA-8M Hardware Integration Guide makes the following suggestions for the SAW filter:

Manufacturer	Order no.	System supported	Comments
TDK/ EPCOS	B8401: B39162B8401P810	GPS+GLONASS	High attenuation
TDK/ EPCOS	B3913: B39162B3913U410	GPS+GLONASS+BeiDou	For automotive application
TDK/ EPCOS	B9416: B39162B9416K610	GPS	High input power
TDK/ EPCOS	B4310: B39162B4310P810	GPS+GLONASS	Compliant to the AEC-Q200 standard
TDK/ EPCOS	B4327: B39162B4327P810	GPS+GLONASS+BeiDou	Low insertion loss
TDK/ EPCOS	B9482: B39162B9482P810	GPS+GLONASS	Low insertion loss
Murata	SAFFB1G56KB0F0A	GPS+GLONASS+BeiDou	Low insertion loss, only for mobile application
Murata	SAFEA1G58KA0F00	GPS+GLONASS	Only for mobile application
Murata	SAFFB1G58KA0F0A	GPS+GLONASS	Only for mobile application
Triquint	856561	GPS	Compliant to the AEC-Q200 standard
TAI-SAW	TA1573A	GPS+GLONASS	Low insertion loss
TAI-SAW	TA1343A	GPS+GLONASS+BeiDou	Low insertion loss

The hardware integration guide also has a lot of other good-to-read information both regarding the SAW filter and everything else.

Regarding U4, it's probably a high side load switch of some model. Only needed if you need to turn the GPS receiver on and off.