AirLink RV55 Hardware User Guide
Rev. 1 June 2019
34
41113042
Low Side Current Sink Output
You can use Pin 4 as a low side current sink, for example, to drive a relay.
Figure 2-16: Low Side Current Sink
Note: The router protection circuitry has a high-impedance (~125 k
) path to ground. If Pin 4 is
connected to 12 V, there will be a small current flow (~100 µA) into Pin 4 during bootup. This flow is
countered when the internal pull-up resistor (10 k
) becomes active after bootup. Depending on
your application, you may need to install an external pull-up resistor (10 k
) in order to nullify the
small input current flow for the first 30 seconds during bootup.
RV55
V
in
V
in
Internal pull-up
resistor
Off
Protection
Circuitry
Pin 4 (power connector)
External solenoid/relay circuit
I
Sink
= 500 mA (Typ)*
* See
on page 34 for more details.
Table 2-9: Low Side Current Sink
Pull-up
State
Minimum
Typical
Maximum
Units
Comments
Off
On
250
500
1000
mA
I_Typical = 25°C
I_Min = 70°C
I_Max = -40°C
Off
Off
—
0
—
mA
Vin = 12