Telos ZephyrExpress user manual Audio i/o section, Outputs, About the XLR Connectors

+5V

+30V Max

Parallel logic input circuit.

Outputs

The outputs are open-collector closures to ground, active low. They require a pull-up resistor to use with logic-circuit inputs. The pull-up may be built into the external device; if not, use a 2.2kΩ resistor to the port’s +5v supply.

Current should be limited to 400mA for each individual output and no more than 1 amp total. This isn’t a problem with logic circuits or individual LEDs, but you should check current consumption if using solid-state audible alarms, relays, or incandescent lights.

w If used with a relay or LED, wire the other side of that component to the port’s +5v supply; or wire to an external supply (no more than +24 v) and connect that supply’s ground to the port’s ground on pin 1.

WARNING!

LEDs and low-voltage relays connected to ZephyrExpressÕ power supply need a current-limiting resistor in series.

Audio i/o section

Microphone	Monitor 1 Mixer Outputs
Inputs	Left	Right

1	Line Inputs 2	Chan A	Chan B	Mon Mix 2	MonMix 1
(XLR or 1/4Ó 2- or 3-conductor)		Direct Receive Outputs		Headphone Outputs (Stereo)

About the XLR Connectors

ZEPHYREXPRESS HARDWARE 3-15