Microchip Technology SC70-6, Руководство пользователя

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SC70-6 and SOT-23-6/8 to DIP-8 Evaluation Board User’s Guide
DS51874A-page 16
©
2009 Microchip Technology Inc.
2.4.3 Passive Components (RXU, RXD, C1, and C2)
The footprints for these components are present to allow maximum flexibility in the use
of this PCB to evaluate a wide range of devices. The purpose of these components may
vary depending on the device under evaluation and how it is to be used in the desired
circuit. Refer to the device data sheet for the recommended components that should
be used when evaluating that device.
• Component RXU allows a pull-up resistor to be installed for the device pin
• Component RXD allows a pull-down resistor or a a capacitive load/filter to be
installed for the device pin
• Component C1 and C2 allows power supply filtering capacitors to be installed
2.4.4 Device Footprints
This section describes the characteristics of the component footprints so that you are
better able to determine if the desired component(s) will be compatible with the board.
2.4.4.1 SC70-6 AND SOT-23-8
The 6-pin SC70 footprint has been superimposed on the 8-pin SOT-23 footprint.
Figure 2-4 shows how the SC70-6 and the SOT-23-8 footprint have been
superimposed. This was done since the pin pitch and width are identical for these two
packages. Only the body width is different (the SC70 is narrower).
The 6-pin SC70 and 8-pin SOT-23 footprint is laid out for packages that have a typical
pitch of 0.65 mm (BSC), a maximum lead width of 0.30 mm.
The 6-pin SC70 footprint has a molded package width of 1.25 mm (BSC), while the
8-pin SOT-23 footprint has a maximum molded package width of 1.75 mm.
Packages that meet these characteristics should be able to be used with this board.
FIGURE 2-4: Superimposing of SC70-6 and SOT-23-8 Footprints.
SOT-23-8 Footprint
SC70 Footprint