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DNT2400 - 08/18/09
Pad
Name
I/O
Description
27
RSVD
-
Reserved pad. Leave unconnected.
28
RSVD
-
Reserved pad. Leave unconnected.
29
RSVD
-
Reserved pad. Leave unconnected.
30 /HOST_RTS I
UART flow control input. The host sets this line low to allow data to flow from the DNT2400 on the
RADIO_TXD pin. When the host sets this line high, the DNT2400 will stop sending data.
31
RADIO_TXD
O
UART transmitter output. The DNT2400 sends serial data to the host on this pin.
32
RADIO_RXD
I
UART receiver input. The DNT2400 receives serial data from the host on this pin.
33 /HOST_CTS O
UART flow control output. The DNT2400 sets this line low to indicate it is ready to accept data from
the host on the RADIO_RXD input. When the DNT2400 sets this line high, the host must stop
sending data.
34 VMOD O
Module’s +3.3 V regulated supply output. Connect to pad 3 to support 3.3 V full scale and/or
ratiometric ADC readings, etc. Current drain on this output should be no greater than 5 mA.
35
RSVD
-
Reserved pad. Leave unconnected.
36
RSVD
-
Reserved pad. Leave unconnected.
37
RSVD
-
Reserved pad. Leave unconnected.
38
RSVD
-
Reserved pad. Leave unconnected.
39
/RESET
I
Active low module hardware reset.
40
RSVD
-
Reserved pad. Leave unconnected.
41
GND
-
RF ground (DNT2400C only). Connect to the host circuit board ground plane.
42 RFIO
I/O
Alternate RF port to the U.FL connector (DNT2400C only). The antenna can be connected to this port with
a 50 ohm stripline or coaxial cable. Leave unconnected when using the U.FL connector.
43
GND
-
RF ground (DNT2400C only). Connect to the host circuit board ground plane.
Table 3.2.1
3.3 DNT2400C RFIO Stripline
C o p p e r
G r o u n d
P l a n e
C o p p e r
S t r i p l i n e
T r a c e
F R - 4 P C B
M a t e r i a l
C i r c u i t B o a r d S t r i p l i n e T r a c e D e t a i l
F o r 5 0 o h m i m p e d a n c e W = 1 . 7 5 * H
Figure 3.3.1
The DNT2400C has a U.FL coaxial connector mounted near pad 42 for antenna connection (see Antenna
Connector discussion below). It is also possible to connect an antenna using a stripline from pad 42. It is