Audio interface, Button/keypad interface, Led control outputs – 2N Helios IP Video Kit User Manual
Page 21: Digital outputs, Digital inputs, Relay output

21
Audio Interface
Microphone input – Standard electret microphone, Max. Vpp=100mV,
Rin=4,4kΩ, Vbias=1,5V
Line input – Max. 755mV RMS, Rin=47kΩ
Amplifier output – 10W amplifier of class D, MONO output, THD < 1%,
minimum loudspeaker impedance: 4Ω
Line output – Max. 755mV RMS, Rout=600Ω
Acoustic echo cancelling – AEC, full duplex
Button/Keypad Interface
Button count – Up to 16 separate buttons in 4x4 matrix
Button function – User programmable
Matrix outputs
4 (ROW1-4 terminals)
Uout <0.1V (L), Uout >3.2V (H), up to 8mA
Matrix inputs
4 (COL1-4 terminals)
Uin < 1.15 (L), Uin > 2.15V, max. Uin = 5V
LED Control Outputs
Output count – 3 (LED1+-, LED2+- and LED3+- terminals)
Output function – User programmable
Output current – Typ. 20mA
Output voltage – Up to 12V
Digital Outputs
Output count – 2 (OUT1+- and OUT2+- terminals)
Output function – User programmable
Output type – Power output with short-circuit protection
Output voltage – 12V
Output current – Up to 650mA
Digital Inputs
Input count – 2 (IN1+- and IN2+- terminals)
Input function – User programmable
Input type – Galvanically isolated inputs (opto-couplers)
Characteristics – Uin < 1.1V (L), Uin > 3V (H), max. Uin = 32V
Relay Output
Output count – 1 (NC, NO, COM terminals)
Output function – User programmable
Limits (DC) – Up to 30VDC/1A
Limits (AC) – Up to 125VAC/0.3A