Micrel
MICRF506BML/YML
Layout Considerations
The MICRF506 is a highly integrated RF IC with only a few “hot” pins, however it is suggested to study available
reference design on www.micrel.com before starting with schematics and layout.
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To ensure the best RF design it is important to plan the layout and dedicate area for the different circuitry.
Good RF engineering is to start with the RF circuitry making sure that general RF guidelines are met
(following points). Separate noisy circuitry and RF by placing it on the opposite side maximizing the
distance between the circuitry. The RF circuitry should be placed as close to what is considered the
ground spot (EG battery) to avoid ground currents. Place the RF circuitry in a position that ensure as
short and straight trace to the antenna connection to avoid reflections.
Proper ground is needed. If the PCB is 2-layer, the bottom layer should be kept only for ground. Avoid
signal traces that split the ground plane. For a 4-layer PCB, it is recommended to keep the second layer
only for ground.
A ground via should be placed close to all the ground pins. The bottom ground (heat sink) pad should be
penetrated with >9 ground via’s. These via’s should be “open” or “plugged” to avoid air pockets caused by
the solder past. If such air pockets appear, the air will expand during the reflow process and may/will
cause the device to twist/move.
The antenna pin (pin 5) has an impedance of ~50 ohm. The antenna trace should be kept to 50 ohm to
avoid signal reflection and loss of performance. Minor deviations can be compensated by matching the
LC filter. Any transmission line calculator can be used to find the needed trace width given a board build
up. Ex: A trace width of 75 mil (1.9 mm) gives 50 impedance on a FR4 board (dielectric cons=4.4) with
copper thickness of 35 μ m and height (layer 1-layer 2 spacing) of 1.00 mm.
RF circuitry is sensitive to voltage supply and therefore caution should be taken when choosing power
circuitry. To achieve the best performance, low noise LDO’s with high PSSR should be chosen. What is
present on the voltage supply will be directly modulated to the RF spectrum causing degradation and
regulatory issues. To make sure you have the right selection, please contact local sales for the latest
Micrel offerings in power management and guidance. To avoid “pickup” from other circuitry on the VDD
lines, it is recommended to route the VDD in a star configuration with decoupling at each circuitry and at
the common connection point (see above layout). If there are noisy circuitry in the design, it is strongly
recommended to use a separate power supply and/or place low value resistors (10ohms), inductors in
series with the power supply line into these circuitry.
It is recommended to connect the PLL loop filter to VDD (C1, C3 and R1). The VDD connection should be
placed as close to pin 31 (VCOVDD) as possible. The MICRF506 has a integrated VCO where the
resonator circuit (varactor ) has a reference to VDD. With a common reference point, the MICRF506
(PLL) will somewhat compensate for noise present on the VDD.
PLL loop filter components C1, C2, C3, R1 and R2 should have a compact layout and should be placed
as close to pin 27 and 29. Avoid signal traces/bus and noisy circuitry around/close/under this area.
Digital high speed logic or noisy circuitry should/must be at a safe distance from RF circuitry or RF VDD
as this might/will cause degradation of sensitivity and create spurious emissions. Example of such
circuitry is LCD display, charge pumps, RS232, clock / data bus etc.
July 2006
32
M9999-092904
+1 408-944-0800
相关PDF资料
MICRF507YML TR TXRX FSK LOW PWR W/AMP 32MLF
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MK01-C SENSOR REED SPST-NO SMD
MK01-H SENSOR REED SPDT-CHANGE SMD
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MK02/6-0 SENSOR REED PCB 24MM T/H
MK03-1C90C-500W SENSOR REED SPDT CYLINDER
MK05-1A66C-500W SENSOR REED SPST-NO SCREW MOUNT
相关代理商/技术参数
MICRF506DEV1 制造商:Micrel Inc 功能描述:KIT MICRF506 EVALUATION
MICRF506YML 制造商:Micrel Inc 功能描述:410/450MHZ ITRANSCEIVER SMD MLF32 制造商:Micrel Inc 功能描述:410/450MHZ ITRANSCEIVER, SMD, MLF32 制造商:Micrel Inc 功能描述:MICRF506 Series 410-450 MHz ISM Band FSK Transceiver - MLF-32 制造商:Micrel Inc 功能描述:410/450MHZ ITRANSCEIVER, SMD, MLF32; Frequency Min:410MHz; Frequency Max:450MHz; Modulation Type:FSK; Sensitivity dBm:-113dBm; Data Rate:200Kbps; Supply Voltage Min:2V; Supply Voltage Max:2.5V; RF IC Case Style:MLF; No. of Pins:32; ;RoHS Compliant: Yes
MICRF506YML TR 功能描述:射频收发器 410MHz to 470MHz, 2.0V to 2.5V, Low-Power FSK Transceiver with +10dBm Power Amplifier RoHS:否 制造商:Atmel 频率范围:2322 MHz to 2527 MHz 最大数据速率:2000 Kbps 调制格式:OQPSK 输出功率:4 dBm 类型: 工作电源电压:1.8 V to 3.6 V 最大工作温度:+ 85 C 接口类型:SPI 封装 / 箱体:QFN-32 封装:Tray
MICRF506YMLTR 制造商:Micrel 功能描述:433MHz ISM Band Transceiver
MICRF506YML-TR 功能描述:IC RF TxRx Only General ISM < 1GHz 410MHz ~ 450MHz 32-VFQFN Exposed Pad, 32-MLF? 制造商:microchip technology 系列:- 包装:剪切带(CT) 零件状态:有效 类型:仅限 TxRx 射频系列/标准:通用 ISM < 1GHz 协议:- 调制:FSK 频率:410MHz ~ 450MHz 数据速率(最大值):200kbps 功率 - 输出:11dBm 灵敏度:-113dBm 存储容量:- 串行接口:SPI GPIO:- 电压 - 电源:2 V ~ 2.5 V 电流 - 接收:8mA ~ 12mA 电流 - 传输:8mA ~ 21.5mA 工作温度:-40°C ~ 85°C 封装/外壳:32-VFQFN 裸露焊盘,32-MLF? 标准包装:1
MICRF507 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:470MHz to 510MHz Low-Power FSK Transceiver with 10dBm Power Amplifier
MICRF507YML TR 功能描述:射频收发器 470MHz to 510MHz, 2.0V to 2.5V, Low-Power FSK Transceiver with +10dBm Power Amplifier RoHS:否 制造商:Atmel 频率范围:2322 MHz to 2527 MHz 最大数据速率:2000 Kbps 调制格式:OQPSK 输出功率:4 dBm 类型: 工作电源电压:1.8 V to 3.6 V 最大工作温度:+ 85 C 接口类型:SPI 封装 / 箱体:QFN-32 封装:Tray
MICRF507YMLTR 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:470MHz to 510MHz Low-Power FSK Transceiver with +10dBm Power Amplifier