73M1866B-IM/F Maxim Integrated Products, 73M1866B-IM/F Datasheet
73M1866B-IM/F
Specifications of 73M1866B-IM/F
Related parts for 73M1866B-IM/F
73M1866B-IM/F Summary of contents
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... This application note provides layout recommendations that must be followed when integrating the 73M1866B and 73M1966B into new designs. For the sake of brevity, the term 73M1x66B refers to both the 73M1866B and 73M1966B. The 73M1x66B can receive signals with amplitudes lower than 3 mV rms imperative that the PCB layout and routing minimize noise interference, especially from AC mains, and Electromagnetic Interference (EMI) from other external sources ...
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... Host PCM/SPI Host-Side It is important to note that the following layout guidelines are applicable to both the 73M1866B and 73M1966B. There is however a section later in the document that adds specific considerations for the 73M1866B. Layout Considerations for Optimal Performance of the MicroDAA The following layout guidelines should be addressed before other signals are routed for the line side circuits. The circuit traces connecting the bridge rectifier (BR1 in Figure 4), the circuit connecting to the VNS pin, R5, and those that connect to the collector of Q6, should larger ...
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... Use power and ground planes on the host-side circuit. • Pay special attention to the way the power and bypass capacitors are connected to the 73M1866B/1966B Figure 3 A. PCB traces from the bypass capacitors to the VDD positive supply should be kept as short as possible. • ...
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... C1 and C3) require a voltage rating of at least 200 V to withstand the ringing and battery voltages. Any capacitors that bridge Tip and Ring need to be rated at least 275 VAC. Locate these resistors and capacitors as close as possible to the 73M1916 Line-Side Device (or the Line-Side of the 73M1866B) to reduce noise pick-up and achieve the best possible performance. ...
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... The 73M1x66B Data Sheet specifies some limits in order to guarantee performance. These parameters include the inductance and interwinding capacitance of the transformer. Also, the rated isolation of the transformer may be important. Rev. 3.5 73M1866B/73M1966B Schematic and Layout Guidelines Dielectric 2 kVrms min 60 µ max ...
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... Schematic and Layout Guidelines Reference Schematics and Layout Examples The following figures contain the reference schematics and layouts that are used with the 73M1866B and 73M1966B Demo Boards. Some components are optional and may or may not be needed for a particular application. ...
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... SRB SRE 1 52.3K, 1% MMBTA06 TP15 VPS C37 0.01uF C12 R10 C8 C38 0.1uF + 0.1uF 174, 1% 4.7uF ISOLATION BARRIER Figure 4: 73M1966B Reference Schematic 73M1866B/73M1966B Schematic and Layout Guidelines OFH 1 Q7 MMBTA42 BR1 HD04 C41 Q6 R58 240 220pF, 300V BCP- MMBTA92 R2 10M, 0805 R12 5 ...
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... Schematic and Layout Guidelines 1 Q5 MMBTA06 C37 0.01uF R10 174, 1% C12 0.1uF VNS Maintain 2.5 mm Spacing Between Line and Host Side Components PCM TX 21 73M1866B DR SPI CSB 20 CS SPI CLK 19 SCLK INTB 18 INT 17 VND SPI OUT 16 SDO SPI IN 15 SDI ...
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... Line-Side Circuit Figure 6: 73M1966B Reference PCB Top View Add heat sink copper for over- voltage protection device Figure 7: 73M1966B Reference PCB Top Copper Layer 9 73M1866B/73M1966B Schematic and Layout Guidelines Isolation Barrier Add extra copper for Q6 heat sink Host-Side Circuit Capacitors crossing the ...
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... PCB mounting pads nearest the barrier separation. This also applies to the backside contact pads on the bottom of the 73M1866B package also important that the assembly and attachment of the parts do not compromise the separation as well. The soldering process often leaves debris under the package, such as solder and flux, and this can degrade the isolation performance of the device even though the PCB layout provides adequate separation ...
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... Figure 10: 73M1866B Reference PCB Bottom View Exposed Bottom Pads on 73M1x66B QFN Packages The 73M1866B and 73M1966B QFN packages have exposed pads on the underside that are intended for device manufacturing purposes. These exposed pads are not intended or needed for thermal relief (heat dissipation) and should not be soldered to the PCB. Soldering of the exposed pad could also contribute to “ ...
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... A shielded enclosure will reduce most of the EMI/EMC; so minimal additional EMI filtering may only be needed. The 73M1866B/1966B Demo Boards include provisions for EMI/EMC suppression on the board. These are used when testing the bare board for EMI/EMC, but are not necessary if the modem is mounted in an EMI/EMC shielded case. Attention to high-frequency and low-frequency bypassing can minimize EMI at the source. • ...
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... It is possible to avoid fuses altogether if the product fire enclosure and is supplied with a 26 AWG or larger RJ-11 telephone cable. But if this route is chosen, the reliability, potential fire and damage to the other circuits in the enclosure should also be considered. Rev. 3.5 73M1866B/73M1966B Schematic and Layout Guidelines F 100 V capacitors in series may be less expensive than a 0.022 µ F 200V µ ...
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... M20PB. 3.3 2/20/2009 In Special Layout Considerations for the 73M1866B, added two reference documents for additional information. In Exposed Bottom Pad on 73M1x66B QFN Packages, added “Soldering of the exposed pad could also contribute to “QFN float”, where the outside pad connections are compromised because of the package sitting higher than the optimum height due to excess solder on the center pads. There are ways to avoid this using a segmented stencil for the solder application, but since there isn’ ...