參數(shù)資料
型號(hào): T5743P3
廠商: Atmel Corp.
英文描述: UHF ASK/FSK Receiver
中文描述: 超高頻ASK / FSK接收器
文件頁數(shù): 7/41頁
文件大?。?/td> 681K
代理商: T5743P3
7
T5743
4569A–RKE–12/02
Analog Signal Processing
IF Amplifier
The signals coming from the RF front-end are filtered by the fully integrated 4th-order IF
filter. The IF center frequency is f
IF
= 1 MHz for applications where f
RF
= 315 MHz or
f
RF
= 433.92 MHz is used. For other RF input frequencies refer to Table 1 to determine
the center frequency.
The T5743 is available with two different IF bandwidths. T5743P3, the version with
B
IF
= 300 kHz, is well suited for ASK systems where Atmel’s PLL transmitter U2741B is
used. The receiver T5743P6 employs an IF bandwidth of B
IF
= 600 kHz. Both versions
can be used together with the U2741B in ASK and FSK mode. If used in ASK applica-
tions, it allows higher tolerances for the receiver and PLL transmitter crystals. SAW
transmitters exhibit much higher transmit freqeuncy tolerances compared to PLL trans-
mitters. Generally, it is necessary to use B
IF
= 600 kHz together with such transmitters.
RSSI Amplifier
The subsequent RSSI amplifier enhances the output signal of the IF amplifier before it is
fed into the demodulator. The dynamic range of this amplifier is DR
RSSI
= 60 dB. If the
RSSI amplifier is operated within its linear range, the best S/N ratio is maintained in ASK
mode. If the dynamic range is exceeded by the transmitter signal, the S/N ratio is
defined by the ratio of the maximum RSSI output voltage and the RSSI output voltage
due to a disturber. The dynamic range of the RSSI amplifier is exceeded if the RF input
signal is about 60 dB higher compared to the RF input signal at full sensitivity.
In FSK mode the S/N ratio is not affected by the dynamic range of the RSSI amplifier.
The output voltage of the RSSI amplifier is internally compared to a threshold voltage
V
Th_red
. V
Th_red
is determined by the value of the external resistor R
Sens
. R
Sens
is con-
nected between Pin SENS and GND or V
S
. The output of the comparator is fed into the
digital control logic. By this means it is possible to operate the receiver at a lower
sensitivity.
If R
Sens
is connected to GND, the receiver operates at full sensitivity.
If R
Sens
is connected to V
S
, the receiver operates at a lower sensitivity. The reduced sen-
sitivity is defined by the value of R
Sens
, the maximum sensitivity by the signal-to-noise
ratio of the LNA input. The reduced sensitivity depends on the signal strength at the out-
put of the RSSI amplifier.
Since different RF input networks may exhibit slightly different values for the LNA gain,
the sensitivity values given in the electrical characteristics refer to a specific input
matching. This matching is illustrated in Figure 6 and exhibits the best possible
sensitivity.
R
Sens
can be connected to V
S
or GND via a microcontroller. The receiver can be
switched from full sensitivity to reduced sensitivity or vice versa at any time. In polling
mode, the receiver will not wake up if the RF input signal does not exceed the selected
sensitivity. If the receiver is already active, the data stream at Pin DATA will disappear
when the input signal is lower than defined by the reduced sensitivity. Instead of the
data stream, the pattern according to Figure 7 is issued at Pin DATA to indicate that the
receiver is still active (see also figure 34).
Figure 7.
Steady L State Limited DATA Output Pattern
DATA
tDATA_L_max
DATA_min
t
相關(guān)PDF資料
PDF描述
T5743P6-TG UHF ASK/FSK Receiver
T5743P3-TG UHF ASK/FSK Receiver
T5743P3-TGQ UHF ASK/FSK Receiver
T5743P6-TGQ UHF ASK/FSK Receiver
T5744 UHF ASK Receiver
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
T5743P3-TG 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:UHF ASK/FSK Receiver
T5743P3-TGQ 功能描述:IC RCVR ASK/FSK 300MHZ 20-SOIC RoHS:否 類別:RF/IF 和 RFID >> RF 接收器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS 產(chǎn)品變化通告:Product Discontinuation 09/Jan/2012 標(biāo)準(zhǔn)包裝:50 系列:* 頻率:850MHz ~ 2.175GHz 靈敏度:- 數(shù)據(jù)傳輸率 - 最大:- 調(diào)制或協(xié)議:- 應(yīng)用:* 電流 - 接收:* 數(shù)據(jù)接口:PCB,表面貼裝 存儲(chǔ)容量:- 天線連接器:PCB,表面貼裝 特點(diǎn):- 電源電壓:4.75 V ~ 5.25 V 工作溫度:0°C ~ 85°C 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP(6x6) 包裝:托盤
T5743P3-TGS 功能描述:IC RCVR ASK/FSK 300MHZ 20-SOIC RoHS:否 類別:RF/IF 和 RFID >> RF 接收器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS 產(chǎn)品變化通告:Product Discontinuation 09/Jan/2012 標(biāo)準(zhǔn)包裝:50 系列:* 頻率:850MHz ~ 2.175GHz 靈敏度:- 數(shù)據(jù)傳輸率 - 最大:- 調(diào)制或協(xié)議:- 應(yīng)用:* 電流 - 接收:* 數(shù)據(jù)接口:PCB,表面貼裝 存儲(chǔ)容量:- 天線連接器:PCB,表面貼裝 特點(diǎn):- 電源電壓:4.75 V ~ 5.25 V 工作溫度:0°C ~ 85°C 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP(6x6) 包裝:托盤
T5743P6-TG 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:UHF ASK/FSK Receiver
T5743P6-TGQ 功能描述:IC RCVR ASK/FSK 600MHZ 20-SOIC RoHS:否 類別:RF/IF 和 RFID >> RF 接收器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS 產(chǎn)品變化通告:Product Discontinuation 09/Jan/2012 標(biāo)準(zhǔn)包裝:50 系列:* 頻率:850MHz ~ 2.175GHz 靈敏度:- 數(shù)據(jù)傳輸率 - 最大:- 調(diào)制或協(xié)議:- 應(yīng)用:* 電流 - 接收:* 數(shù)據(jù)接口:PCB,表面貼裝 存儲(chǔ)容量:- 天線連接器:PCB,表面貼裝 特點(diǎn):- 電源電壓:4.75 V ~ 5.25 V 工作溫度:0°C ~ 85°C 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP(6x6) 包裝:托盤