DS21FT42 Maxim Integrated Products, DS21FT42 Datasheet - Page 114

• Manufacturer Part Number: DS21FT42
• Description: IC FRAMER T1 4X3 12CH 300-BGA
• Manufacturer: Maxim Integrated Products

Specifications of DS21FT42

• Controller Type: T1 Framer
• Interface: Parallel/Serial
• Voltage - Supply: 2.97 V ~ 3.63 V
• Current - Supply: 225mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 300-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

DS21FF42/DS21FT42
POWER SUPPLY DE-COUPLING
In a typical PCB layout for the MCM, all of the VDD pins will connect to a common power plane and all
the VSS lines will connect to a common ground plane. The recommended method for de-coupling is
shown below in both schematic and pictorial form. As shown in the pictorial, the capacitors should be
symmetrically located about the device. Figure 25-1 uses standard capacitors, two .47 uf ceramics and
two .01uf ceramics. Since VDD and VSS signals will typically pass vertically to the power and ground
planes of a PCB, the de-coupling caps must be placed as close to the DS21Fx4y as possible and routed
vertically to power and ground planes.
De-coupling scheme using standard tantalum caps. Figure 25-1
VDD
VDD
.47
.47
DS21Fx4y
DS21Fx4y
.01
.01
.47
.01
.47
.01
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