SAW Components
SAW RF filter
B3727
433.92 MHz
Data sheet
ESD protection of SAW filters
SAW filters are E lectro S tatic D ischarge sensitive devices. To reduce the probability of damages
caused by ESD, special matching topologies have to be applied.
In general, “ESD matching” has to be ensured at that filter port, where electrostatic discharge is
expected.
Electrostatic discharges predominantly appear at the antenna input of RF receivers. Therefore
only the input matching of the SAW filter has to be designed to short circuit or to block the ESD
pulse.
Below three figures show recommended “ESD matching” topologies.
For wideband filters the high-pass ESD matching structure needs to be at least of 3 rd order to
ensure a proper matching for any impedance value of antenna and SAW filter input. The required
component values have to be determined from case to case.
Cs1
Cs3
Cs1
Cs3
Lp2
to output
matching
Lp2
to output
matching
Fig. 1 MLC varistor plus ESD matching
Fig. 2 Suppressor diode plus ESD matching
In cases where minor ESD occur, following simplified “ESD matching” topologies can be used
alternatively.
Cs1
Cs3
Lp2
to output
matching
Fig. 3 3 rd order high-pass structure for basic ESD protection
In all three figures the shunt inductor Lp2 could be replaced by a shorted microstrip with proper
length and width. If this configuration is possible depends on the operating frequency and
available pcb space.
Effectiveness of the applied ESD protection has to be checked according to relevant industry
standards or customer specific requirements
For further information, please refer to EPCOS Application report:
“ ESD protection for SAW filters ”.
This report can be found under www.epcos.com/rke.Click on “Applications Notes”.
Please read cautions and warnings and
important notes at the end of this document.
7
December 17, 2012
相关PDF资料
B39431B3730H110 FILTER SAW 433.92MHZ SMD
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B39431B3743H110 FILTER SAW 433.92MHZ REMOTE SMD
B39431B3748H110 FILTER SAW 434.42MHZ SMD
B39431B3760Z810 FILTER SAW 433.92MHZ REMOTE SMD
B39431B3770Z810 FILTER SAW 426.08MHZ SMD
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相关代理商/技术参数
B39431B3730H110 功能描述:信号调节 DCC6E Q 3x3 Filter RoHS:否 制造商:EPCOS 产品:Duplexers 频率:782 MHz, 751 MHz 频率范围: 电压额定值: 带宽: 阻抗:50 Ohms 端接类型:SMD/SMT 封装 / 箱体:2.5 mm x 2 mm 工作温度范围:- 30 C to + 85 C 封装:Reel
B39431-B3730-H110 制造商:EPCOS 制造商全称:EPCOS 功能描述:SAW Components Low-loss Filter 433,92 MHz
B39431B3730H110MR-CUT TAPE 制造商:EPCOS 功能描述:B39431 Series 433.92 MHz 400 kHz Passband -45 to + 125?C SAW Filter
B39431B3730Z810 制造商:TDK Epcos 功能描述:
B39431B3732H110 功能描述:信号调节 433.92 MHz SMD RoHS:否 制造商:EPCOS 产品:Duplexers 频率:782 MHz, 751 MHz 频率范围: 电压额定值: 带宽: 阻抗:50 Ohms 端接类型:SMD/SMT 封装 / 箱体:2.5 mm x 2 mm 工作温度范围:- 30 C to + 85 C 封装:Reel
B39431B3733H110 功能描述:信号调节 DCC6E Q 3x3 Filter RoHS:否 制造商:EPCOS 产品:Duplexers 频率:782 MHz, 751 MHz 频率范围: 电压额定值: 带宽: 阻抗:50 Ohms 端接类型:SMD/SMT 封装 / 箱体:2.5 mm x 2 mm 工作温度范围:- 30 C to + 85 C 封装:Reel
B39431B3735H110 功能描述:信号调节 433.42 MHz RoHS:否 制造商:EPCOS 产品:Duplexers 频率:782 MHz, 751 MHz 频率范围: 电压额定值: 带宽: 阻抗:50 Ohms 端接类型:SMD/SMT 封装 / 箱体:2.5 mm x 2 mm 工作温度范围:- 30 C to + 85 C 封装:Reel
B39431B3736H110 功能描述:信号调节 B3736 433.92MHz RoHS:否 制造商:EPCOS 产品:Duplexers 频率:782 MHz, 751 MHz 频率范围: 电压额定值: 带宽: 阻抗:50 Ohms 端接类型:SMD/SMT 封装 / 箱体:2.5 mm x 2 mm 工作温度范围:- 30 C to + 85 C 封装:Reel