side view (through can)
8 mm
side view (with can)
top view (without can)
3.5mm
RF GND 1
Antenna 2
RF GND 3
4
5
6
No pin
7
8
9
30.48mm
3.4 mm
18
17
16
15
14
13
12
11
10
GND
Vcc
ENABLE
SETUP
TXD
NC
RXD
STATUS
GND
2.2mm
recommended PCB hole size: 1.2 mm
module footprint size: 26 x 37mm
pin pitch: 2.54 mm
pins 4, 5, 6, 7, 8 & 9 are not fitted
Figure 3: TDH2 footprint (top view)
Pin description
Pin
18
17
16
15
14
13
12
11
10
Name
GND
Vcc
ENABLE
SETUP
TXD
NC
RXD
STATUS
GND
Function
Ground
5V (regulated power supply)
Enable or DTR (5V CMOS logic level input)
Test/Setup mode selection
Transmit Data (Inverted RS232 at 5V CMOS logic level)
No Pin
Receive Data (Inverted RS232 at 5V CMOS logic level)
Busy or CTS (5V CMOS logic level output)
Ground
RF GND
pin 1 & 3
RF Ground pin, internally connected to the module screen and pins 10 and 18 (0V). This pin should be
connected to the RF return path (e.g. co-axial cable braid, main PCB ground plane, etc).
RF
pin 2
50Ω RF input/output from the antenna, it is DC isolated internally. (see antenna section for details).
GND
pin 8, 9, 10 and 18
Supply ground connection to ground plane and can.
VCC
pin 17
5V voltage regulator should be used to have a clean 5V supply to the module. A 4V regulator is used
inside for radio circuitry.
ENABLE
pin 16
Active low Enable pin. It has a 47kΩ pull-ups to Vcc. It should be pulled Low to enable the module.
This can also be connected to DTR pin (only if it is asserted by the host) of an RS232 serial port via a
MAX232 or equivalent RS232-CMOS level converter.
Radiometrix Ltd
TDH2 Data Sheet
page 3
RADIOMETRIX [ RADIOMETRIX LTD ]
