Vansco VMM3120, Руководство пользователя

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User Guide 31
Outputs
When connecting high-side outputs, ensure you follow these best practices:

High-side outputs should not be connected to loads that will draw currents
greater than the maximum peak current, or maximum continuous current.

The grounds for the loads should be connected physically close to the
VMM3120 power grounds.
The following shows a typical high-side output connection:
Internal to product
High-Side
Output
Application
Load
Figure 15: Typical high-side output installation connections
4.1.3.1. High-Side Output De-Rating Requirements
Each high-side output is rated to continuously drive 2.5 A of current; however, in
some applications, the rating for high-side outputs must be reduced, or de-rated,
to less than 2.5 A.
Note: How an output is de-rated is based on how all outputs are being used
collectively on the VMM3120.
There are two issues that must be addressed to determine the de-rating for high-
side outputs: current and power dissipation.
Current
You must determine how much current each output can drive. To determine the
amount, you must look at outputs in pairs, because output current is provided
from the same circuitry for each pair of outputs.

Outputs 1 and 2 share the same circuitry as do outputs 3 and 4, 5 and 6, and so
on, to outputs 15 and 16.