OpenSprinkler Forums Hardware Questions OpenSprinkler Pi (OSPi) Smaller DC version of OSPi Reply To: Smaller DC version of OSPi



Thanks Ray,

I have been hard at work and have created PCB layout about to send it off to be fabricated.

Couple of questions re substitute parts:
1) The 220uH inductor for the boost circuit, are there any specs for current and resistance?
One available locally is RLB0912-221KL 220uH, RMS current 440 mA, 0.74 ohms is this one suitable?

2)QP1, QP2 AP3401 or BSS84
The P-Channel FETs to turn on the boost and fire it.
AP3401 doesn’t seem to exists(miss-type?), should this be AO3401?
I assume that the BSS84 can’t handle enough current?
AO3401 isn’t available locally will a DMG2307L be ok, datasheet below?

3) N-Channel FETs to switch the Solenoids to GND, Q1-8 AO3400 or BSS123
AO3400 not available locally, assume BSS123 can’t handle enough current?
ZXMN3F30FHTA is available locally will it be ok, data sheet below?

4)Should I optimize the Boot circuit to operate more efficiently on 5V input voltage?
I notice you different values in the OSBee for the capacitor and resistor around the 34063 boost converter.
Is the Osbee optimized for 5V input?

Thanks for your time!