NRF0433 Datasheet, PDF (5/14 Pages) List of Unclassifed Manufacturers – Single chip 433MHz RF Transceiver

PRODUCT SPECIFICATION
nRF0433 Single chip RF Transceiver
IMPORTANT TIMING DATA
Power up time
The time from power is switched on until the synthesised frequency is stable is the
power up time, t_on. t_on is 75 ms for nRF0433. Power up time can be reduced if a stable
4MHz reference signal (eg. from the driver pin of an active micro-controller) is
available at the XC1 input when powering up the transceiver. In this case t_on is 7.5 ms.
Figure 4 shows a circuit diagram of a typical application. Note that these times may
vary depending on the crystal used.
XC2
micro
controller
X1
X2
CS
5.6pF
nRF0433
XC1
C1 ^{4.0 MHz}
(22pF)
C2
(22pF)
Figure 4. nRF0433 with an external reference oscillator (example).
Power up in transmit-mode
To avoid spurious emission outside the ISM-band during power-up of nRF0433, the
TXEN-input must be kept low until the synthesised frequency is stable (t_on),
see figure 5.
When enabling transmit-mode, no data should be transmitted before the TXEN-input
has been high for at least 3ms (t_data-t_on).
V_DD
TXEN
D_IN
t
t_on
t_data
Figure 5. Power up timing diagram for nRF0433.
Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway -
Revision: 3.2
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February 2000