nRF904 Nordic VLSI, nRF904 Datasheet - Page 9

• Manufacturer Part Number: nRF904
• Description: RF Transmitter 902-928MHz
• Manufacturer: Nordic VLSI

PRODUCT SPECIFICATION
The “ANT” output pins provide a balanced RF output to the antenna. The pins must
have a DC path to VDD, either via a RF choke or via the centre point in a loop
antenna. The load impedance seen between the ANT1/ANT2 outputs should be in the
range 200-700
power (10dBm) is needed. Lower load impedance (for instance 50 ) can be obtained
by fitting a simple matching network or a RF transformer (balun). The 50
also be connected directly between the ANT1/ANT2 pins, but this will result in higher
current consumption for a given output power to the antenna.
A single ended antenna or 50
a differential to single ended matching network (BALUN) as shown in Figure 8.
The inductors in Figure 8 need to have a Self-Resonance Frequency (SRF) above the
carrier frequency (902-928MHz). Suitable 68nH inductors are listed in Table 7.
Nordic VLSI ASA
Revision: 2.1
Pulse
Coilcraft
muRata
Stetco
KOA
Figure 8. Connection of nRF904 to single ended antenna (50 ) by using
xxxxxx
Table 7. Vendors and part no. for suitable 68nH inductors.
-
http://www.pulseeng.com
http://www.coilcraft.com
http://www.murata.com
http://www.stetco.com
http://www.koaspeer.com
. A load impedance of 400
a differential to single ended matching network.
Vestre Rosten 81, N-7075 Tiller, Norway
nRF904
ANT1
ANT2
test instrument may be connected to nRF904 by using
1K
xxxxxx
VDD
QhtrÃ(Âsà %
68nH
15nH
PE-0603CD680JTT
0603CS-68NXJBC
LQW1608A68NJ00
0603G680JTE
KQ0603TE68NJ
xxxxxx
is recommended if maximum output
-
33pF
3.3pF
3.3pF
Phone [phone]
RF out 50 ohm
xxxxxx
-
Fax [phone]
October 2001
load can