DS21FF44 Maxim Integrated Products, DS21FF44 Datasheet - Page 117

• Manufacturer Part Number: DS21FF44
• Description: IC FRAMER E1 4X4 16CH 300-BGA
• Manufacturer: Maxim Integrated Products

Specifications of DS21FF44

• Controller Type: E1 Framer
• Interface: Parallel/Serial
• Voltage - Supply: 2.97 V ~ 3.63 V
• Current - Supply: 300mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 300-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

DS21FT44/DS21FF44
POWER SUPPLY DECOUPLING
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 decoupling is
shown below in both schematic and pictorial form. As shown in the pictorial, the capacitors should be
symmetrically located about the device. Figure 24-1 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 decoupling caps must be placed as close to the DS21Fx4y as possible and routed
vertically to power and ground planes.
Figure 24-1. DECOUPLING SCHEME USING STANDARD TANTALUM CAPS
VDD
VDD
.47
.47
DS21Fx4y
DS21Fx4y
.01
.01
.47
.01
.47
.01
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