NRF9E5 NORDIC SEMICONDUCTOR, NRF9E5 Datasheet - Page 29

• Manufacturer Part Number: NRF9E5
• Description: TRX, 430-928MHZ, MCU/ADC/PWM, SMD
• Manufacturer: NORDIC SEMICONDUCTOR

Specifications of NRF9E5

• Receiving Current: 12.5mA
• Transmitting Current: 30mA
• Data Rate: 50Kbps
• Frequency Range: 430MHz To 928MHz
• Modulation Type: GFSK
• Rf Ic Case Style: QFN
• No. Of Pins: 32
• Supply Voltage Range: 1.9V To
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PRODUCT SPECIFICATION
nRF9E5 Single Chip Transceiver with Embedded Microcontroller and ADC
9.8
When the nRF905 is in ShockBurst
high as soon as an incoming packet with an address that is identical with the device’s
own identity is received. With the Address Match pin the controller is alerted that the
nRF905 is receiving data actually before the Data Ready (DR) signal is set high. If the
Data Ready (DR) pin is not set high i.e. the CRC is incorrect then the Address Match
(AM) pin is reset to low at the end of the received data packet. This function can be very
useful for an MCU. If Address Match (AM) is high then the MCU can make a decision
to wait and see if Data Ready (DR) will be set high indicating a valid data packet has
been received or ignore that a possible packet is being received and switch modes.
9.9
The Data Ready (DR) signal makes it possible to largely reduce the complexity of the
MCU software program.
In ShockBurst
transmitted, telling the MCU that the nRF905 is ready for new actions. It is reset to low
at the start of a new packet transmission or when switched to a different mode i.e.
receive mode or standby mode.
In ShockBurst
beginning of the pre-amble and is set low at the end of the preamble. The Data Ready
(DR) signal therefore pulses at the beginning of each transmitted data packet.
In ShockBurst
i.e. a valid address, packet length and correct CRC. The MCU can then retrieve the
payload via the SPI interface. The Data Ready (DR) pin is reset to low once the data has
been clocked out of the data buffer or the device is switched to transmit mode.
9.10 Auto Retransmit
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.
9.11 RX Reduced Power Mode
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 - Vestre Rosten 81, N-7075 Tiller, Norway -Phone [phone] - Fax [phone]
Revision: 1.3
Address Match
Data Ready
TM
TM
TM
TX, the Data Ready (DR) signal is set high when a complete packet is
RX, the signal is set high when nRF905 has received a valid packet,
TX Auto Retransmit the Data Ready (DR) signal is set high at the
TM
Page 29 of 108
RX mode, the Address Match (AM) pin is set
June 2006