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SNIU028A – February 2016 – Revised April 2016
Copyright © 2016, Texas Instruments Incorporated
Filter
Chapter 4
SNIU028A – February 2016 – Revised April 2016
Filter
The UCD3138 filter is a PID filter with many enhancements for power supply control. Some of its features
include:
•
PID Based Architecture
•
Additional
α
coefficient and history in D branch
•
Programmable Non-Linear Limits for automated modification of filter coefficients based on received
EADC error
•
Multiple coefficient sets fully configurable by firmware
•
Full 24-bit precision throughout Filter calculations
•
Programmable clamps on Integrator Branch and Filter Output
•
Ability to load values into internal filter registers while system is running
•
Ability to stall calculations on any of the individual filter branches
•
Ability to clear and stall calculations on any of the individual filter branches
•
Duty Cycle, Resonant Period, or phase shift generation based on filter output.
•
Flux Balancing
•
Voltage feed forward
Topic
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Page
4.1
Filter Math Details
.............................................................................................
4.2
Filter Status Register
........................................................................................
4.3
Filter Control Register
.......................................................................................
4.4
XN, YN Read and Write Registers
.......................................................................
4.5
Coefficient Configuration Register
......................................................................
4.6
Kp, Ki, and Kd Registers
...................................................................................
4.7
Alpha Registers
................................................................................................
4.8
Filter Nonlinear Limit Registers
..........................................................................
4.9
Clamp Registers
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4.10
Filter Preset Register
........................................................................................
4.11
Filter Registers Reference
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