#Power supply

Aria G25 needs a single line 3.3 volt DC power supply which can be provided in any combination on the following pins: 

| Power lines | Aria pins |
|-----------|-------------|
| +3V3 DC power in | N1, S1, E24, W24 |
| GND signal ground | N24, S24, E1, W1 |

A simple and cheap module called [PS3V3](/PS3V3) is available from Acme SYstems. 
<br/>
It has a miniUSB connector and can
be integrate in your PCB as a SMD component.

<img src="ariag25_ps3v3.jpg">  

@shop='PS3V3'
@shop='PS-5V1A-EU-MUSB'

#Extended range power supply

If you need to get the power in an industrial or mobile environment here is illustrated
a simple solution using this two modules:

* [NETUSPS1 DC/DC converter](/NETUSPS1)
* [EPS DC/DC converter](/EPS)

In this way is is possible to provide to Aria from a 7 to 28 Volt DC source. 

<img src="ariag25_power_supply_extended.jpg">  

@shop='NETUSPS1'
@shop='EPS'

#Power supervisor

In real life applications we suggest to add a reset supervisor circuit to 
assure correct startup sequences.

Here are two possibilities:

* Using a TPS3808G33 IC more flexible since it lets 
you to program the reset assertion delay with C52. 
* Using a CAT811 IC that is cheaper but has a fixed 140ms delay.

<img src="./ariag25_reset_supervisor.png" class="caption" title="Reset supervisors"/>  

#RTC backup battery

Applying 3 Volt DC on E1 (GND) and E20 (VBAT +3VDC) it is possible to mantaint 
the RTC (Real Time Clock) active when the power supply if off. This will mantain
the system clock up to 6 months with no power using a small CR1220 Lithium battery. 

A bigger battery can be used to extend the time duration. 

<img src="ariag25_rtc_battery.jpg">  

@shop='BAT-HOLDER-1'
@shop='BAT-HOLDER-2'
@shop='CH23-1220'