User's Manual

AC4490 Specifications
AC4490 SpecificationsAC4490 Specifications
AC4490 Specifications
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Validated RSSI
Validated RSSIValidated RSSI
Validated RSSI
As RSSI values are only valid when the local radio is receiving a RF packet from a remote radio,
instantaneous RSSI can be very tricky to use. Therefore, the transceiver stores the most recent valid
RSSI value. The Host issues the
Report Last Good RSSI
Report Last Good RSSI Report Last Good RSSI
Report Last Good RSSI command to request that value (details can
be found in the
On-the-Fly Control Command Reference
On-the-Fly Control Command ReferenceOn-the-Fly Control Command Reference
On-the-Fly Control Command Reference ). Validated RSSI is not available at the RSSI
pin.
Figure
Figure Figure
Figure 1
11
1 – RSSI Voltage vs. Received Signal Strength
– RSSI Voltage vs. Received Signal Strength – RSSI Voltage vs. Received Signal Strength
– RSSI Voltage vs. Received Signal Strength
5.1.8
5.1.85.1.8
5.1.8 UP_Reset (pin 15)
UP_Reset (pin 15)UP_Reset (pin 15)
UP_Reset (pin 15)
UP_Reset provides a direct connection to the reset pin on the AC4490 microprocessor. To guarantee
a valid power-up reset, this pin should never be tied Low on power-up. For a valid power-on reset,
reset must be High for a minimum of 50us.
5.1.9
5.1.95.1.9
5.1.9 Command/Data (pin 17)
Command/Data (pin 17)Command/Data (pin 17)
Command/Data (pin 17)
When logic High, transceiver interprets Host data as transmit data to be sent to other transceivers and
their Hosts. When logic Low, transceiver interprets Host data as command data (see section 4)
(see section 4)(see section 4)
(see section 4).
0
0.2
0.4
0.6
0.8
1
1.2
-105 -100 -95 -90 -85 -80 -75 -70 -65 -60 -55 -50
Signal at Receiver (dBm)
Voltage (VDC)