ATA5423 ATMEL Corporation, ATA5423 Datasheet - Page 8

• Manufacturer Part Number: ATA5423
• Manufacturer: ATMEL Corporation

2.2
Figure 2-2.
8
Typical Base–station Application
ATA5423/25/28/29 [Preliminary]
connector
RF
Typical Base–station Application, 433.92 MHz
L4
50
OUT
C11
AVCC
SAW Filter
C10
L2
Figure 2.2
external components are 12 capacitors, 1 resistor, 4 inductors, a SAW filter, and a crystal. C
and C
ing capacitors for the internal voltage regulators. C
15 nF fixed capacitor used for the internal quasi–peak detector and for the high–pass frequency
of the data filter. C
matching inductors of about 5.6 nH to 56 nH. A load capacitor for the crystal of 9 pF is inte-
grated. R
quarter wave or PCB antenna, which has high efficiency and wide band operation, is typically
used here, it is recommended to use a SAW filter to achieve high sensitivity in case of powerful
out–of–band blockers. L
the harmonics in the transmitted signal to meet regulations. An internally regulated voltage at pin
VSOUT can be used in case the microcontroller only supports 3.3 V operation, a blocking
capacitor with a value of C
L1
C5
L3
C8
C9
3
to C
R1
1
is typically 22 k and sets the output power at RF_OUT to about 10 dBm Since a
shows a typical 433.92 MHz V
4
are 68 nF voltage supply blocking capacitors. C
C7
NC
NC
NC
RF_IN
NC
433_N868
NC
R_PWR
PWR_H
NC
RF_OUT
NC
7
to C
1
11
ATA5423/ATA5425/
ATA5428/ATA5429
, C
C1
are RF matching capacitors in the range of 1 pF to 33 pF. L
12
9
= 2.2 µF has to be connected to VSOUT in any case.
and C
C2
VCC = 4.75 V to 5.25 V
10
C4
together form a low–pass filter, which is needed to filter out
C12
SDO_TMDO
DEM_OUT
CC
SDI_TMDI
N_RESET
CDEM
VSINT
= 4.75 V to 5.25 V base–station application. The
RSSI
SCK
CLK
IRQ
NC
CS
C6
XTAL2
5
is a 10 nF supply blocking capacitor. C
13.25311 MHz
2
C3
VCC
and C
Sensor
µC
12
VSS
are 2.2 µF supply block-
4841A–RKE–02/05
2
to L
6
4
is a
are
1