AD9992BBCZ datasheet(41/92 Pages) AD

41 / 92 page

AD9992

Rev. C | Page 41 of 92

Multiplier Mode

To generate very wide vertical timing pulses, a vertical region

can be configured into a multiplier region. This mode uses

the V-pattern registers in a slightly different manner. Multiplier

mode can be used to support unusual CCD timing requirements,

such as vertical pulses that are wider than the 13-bit V-pattern

toggle position counter. In general, the 13-bit toggle position

counter can be used with the sweep mode feature to support very

wide pulses; however, multiplier mode can be used to generate

even wider pulses.

The start polarity and toggle positions are still used in the same

manner as the standard V-pattern group programming, but

VLEN is used differently. Instead of using the pixel counter

(HD counter) to specify the toggle position locations (XVTOG1,

XVTOG2, XVTOG3, and XVTOG4) of the V-pattern group,

the VLEN is multiplied with the XVVTOG position to allow

very long pulses to be generated. To calculate the exact toggle

position, which is counted in pixels after the start position, use the

following equation:

Multiplier Mode Toggle Position = XVTOG × VLEN

Because the XVTOG register is multiplied by VLEN, the

resolution of the toggle position placement is reduced. If VLEN =

4, the toggle position precision is reduced to 4-pixel increments

instead of to single-pixel increments. Table 18 summarizes how

the V-pattern group registers are used in multiplier mode

operation. In multiplier mode, the VREP registers must always be

programmed to the same value as the highest toggle position.

Figure 50 illustrates this operation. The first toggle position is 2,

and the second toggle position is 9. In nonmultiplier mode, this

causes the V-sequence to toggle at Pixel 2 and then at Pixel 9 within

a single HD line. However, in multiplier mode, toggle positions are

multiplied by the value of VLEN (in this case, 4); therefore, the first

toggle occurs at Pixel 8, and the second toggle occurs at Pixel 36.

Sweep mode has also been enabled to allow the toggle positions

to cross the HD line boundaries.

Table 18. Multiplier Mode Register Parameters

Length

Range

Description

MULTI

High/low

High enables multiplier mode.

VPOL

High/low

Starting polarity of XV1 to XV10 signals in each V-pattern group.

XVTOG

13b

0 to 8191 pixel location

Toggle positions for XV1 to XV10 signals in each V-pattern group.

VLEN

13b

0 to 8191 pixels

Used as multiplier factor for toggle position counter.

VREP

13b

0 to 8191 pixel location

VREP_EVEN/VREP_ODD must be set to the same value as the highest XVTOG value.

XV1 TO XV10

VLEN

12 3412 341 2341 2341 2341 234 1234 1234 123 4123 4

START POSITION OF VPAT GROUP IS STILL PROGRAMMED IN THE V-SEQUENCE REGISTERS

PIXEL

NUMBER

12 3456 789 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

MULTIPLIER MODE V-PATTERN GROUP PROPERTIES:

1START POLARITY (STARTPOL = 0).

2FIRST, SECOND, AND THIRD TOGGLE POSITIONS (XVTOG1 = 2, XVTOG2 = 9).

3LENGTH OF VPAT COUNTER (VLEN = 4); THIS IS THE MINIMUM RESOLUTION FOR TOGGLE POSITION CHANGES.

4TOGGLE POSITIONS OCCUR AT LOCATION EQUAL TO (XVTOG × VLEN).

5IF SWEEP REGION IS ENABLED, THE V-PULSES MAY ALSO CROSS THE HD BOUNDRIES, AS SHOWN ABOVE.

Figure 50. Example of Multiplier Region for Wide Vertical Pulse Timing

AD9992BBCZ датащи(PDF) 41 Page - Analog Devices

AD9992BBCZ датащи(HTML) 41 Page - Analog Devices

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 82 83 84 85 86 87 88 89 90 91 92

датащи скачать

ссылки URL