NRF905 NORDIC SEMICONDUCTOR, NRF905 Datasheet - Page 29

• Manufacturer Part Number: NRF905
• Description: IC, TRANSCEIVER, 430 928MHZ, SMD
• Manufacturer: NORDIC SEMICONDUCTOR

Specifications of NRF905

• Transmitting Current: 9mA
• Data Rate: 50Kbps
• Frequency Range: 430MHz To 928MHz
• Modulation Type: GFSK
• Sensitivity Dbm: -100dBm
• Rf Ic Case Style: QFN
• No. Of Pins: 32
• Supply Voltage Range: 1.9V To 3.6V
• Output Power: 10dBm
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PRODUCT SPECIFICATION
nRF905 Single Chip 433/868/915 MHz Radio Transceiver
9.4
One way to increase system reliability in a noisy environment or in a system without
collision control is to transmit a packet several times. This is easily accomplished with
the Auto Retransmit feature in nRF905. By setting the AUTO_RETRAN bit to “1” in
the configuration register, the circuit keeps sending the same data packet as long as
TRX_CE and TX_EN are high. As soon as TRX_CE is set low the device will finish
sending the packet it is currently transmitting and then return to standby mode.
9.5
To maximize battery lifetime in application where the nRF905 high sensitivity is not
necessary; nRF905 offers a built in reduced power mode. In this mode, the receive
current consumption reduces from 12.5mA to only 10.5mA. The sensitivity is reduced
to typical –85dBm, 10dB. Some degradation of the nRF905 blocking performance
should be expected in this mode. The reduced power mode is an excellent option
when using Carrier Detect to sense if the wanted channel is available for outgoing
data.
Main office: Nordic Semiconductor ASA
Revision: 1.4
Auto Retransmit
RX Reduced Power Mode
- Vestre Rosten 81, N-7075 Tiller, Norway
Page 29 of 42
- Phone [phone] -Fax [phone]
June 2006