AN2262 Motorola / Freescale Semiconductor, AN2262 Datasheet - Page 12

• Manufacturer Part Number: AN2262
• Description: Wireless HC08 Modem
• Manufacturer: Motorola / Freescale Semiconductor

AN2262/D
Antenna Design
12
NOTE:
All SMD capacitors and resistors are of standard 0805 size, unless otherwise
specified.
For power connection to J1 use Farnell 224-911 cable end.
The MC33491 is no longer available. See
Notes on page
The whip antenna is the simplest design. This is a quarter wavelength wire that
stands above a ground plane. The /4 length is purely theoretical. Depending
on the nature of the wire and the geometry of the ground plane, consider the
length as (k * /4) with k comprised between 0.93 and 0.98. For the 868-MHz
band, the antenna is made of wire 84 mm long.
Some commercially available antennae are, for example, PU-BNC-868 or
FLEXI-BNC-868 types from RF Solutions, Ltd. (
1. Components are NOT assembled in RS232 mode. See
2. Components are NOT assembled in RS485 mode. See
Quantity
Configurations.
Configurations.
1
1
1
1
1
1
1
1
1
Wireless HC08 Modem
36.
Table 3. Bill of Materials (Sheet 3 of 3)
Reference
U5
U6
U3
U4
U7
U8
X1
X2
X3
(1)
(2)
MC33491 to MC33493 Migration
http://www.rfsolutions.co.uk
RS232 versus RS485
RS232 versus RS485
MC68HC908GP32CFB
(ON Semiconductor)
(ON Semiconductor)
MC33263NW-50
MC33263NW-30
13.571875 MHz
13.582187 MHz
MAX491ECSA
MC33593FTA
MAX202CSE
32.768 kHz
(Motorola)
(Motorola)
(Maxim)
(Maxim)
Part
MOTOROLA
)