UCD3028RMHT datasheet(33/81 Pages) TI1

33 / 81 page

UCD3040

UCD3028

UCD3020

www.ti.com

SLUS868H – DECEMBER 2009 – REVISED OCTOBER 2013

In resonant mode, the output is multiplied by the maximum-allowed switching period to modulate the DPWM

switching frequency. The filter output is also multiplied by a programmed percentage of the maximum-allowed

switching period to generate the required fixed DPWM duty ratio.

Nonlinear Control Capability

The nonlinear control capability of the UCD30xx is implemented by applying a user-programmable gain to the

incoming error signal. This gain is applied by use of the filter input scaler. The user has a paged table of five 6-bit

values that represent a 4.2 binary number. This allows a gain range of 0.25 to 15.75 in 0.25 increments. The

gain values are selected based on the range of the incoming error voltage from the EADC. The error voltage

range is determined by comparing it to a set of four 6-bit limits.

Error Range

Gain Applied

E(n) < Limit_0

≥ Gain0

[5–0]

Limit_0 < E(n) < Limit_1

≥ Gain1

[11–6]

Limit_1 < E(n) < Limit_2

≥ Gain2

[29–24]

Limit_2 < E(n) < Limit_3

≥ Gain3

[23–18]

E(n) > Limit_3

≥ Gain4

[17–2]

Five gain values and the four limit selections are set up in a paged structure (Figure 6). This allows the user to

configure the off page. The active page is controlled by a bit in the control register. The switching of the pages

occurs when the filter is inactive. The status bit must be polled to determine the active page before writing to a

bank.

Status Signals

There are five status signals available to the user.

•

Two EADC rail signals indicate that the EADC value coming into the filter has reached the maximum or

minimum limits.

•

A nonlinear page-active status shows the nonlinear table that is currently in use.

•

A clamp page-active status shows the clamp page that is currently in use.

•

A page-active status shows the coefficient page that is currently in use.

Control Signals

There are seven control signals available to the user.

•

The filter enable control that turns on and off filter processing. When this bit is disabled the user's software

can write to the input error terms and the stored output results.

•

The page active control sets which bank of coefficients is in use by the filter. The ability to write to the

coefficient banks depends on the setting of this control.

•

The read page control selects which coefficient bank is being read by the user's software.

•

The 3 pole 3 zero enable control turns on the filter processing through the optional 1 pole 1 zero stage.

•

The CPU sample enable control forces the filter to use the E(n) terms written by the user's software.

•

The clamp page active control sets which page of clamps are in use by the filter. The ability to write to the

clamp pages depends on the setting of this control.

•

The non-linear page active control sets which page of non-linear gain table and limits are in use by the filter.

The ability to write to the non-linear gain table and limits depend on the setting of this control.

Submit Documentation Feedback

Product Folder Links: UCD3040 UCD3028 UCD3020

UCD3028RMHT bảng dữ liệu(PDF) 33 Page - Texas Instruments

UCD3028RMHT bảng dữ liệu(HTML) 33 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81

bảng dữ liệu tải về

Link URL