TW8 datasheet(21/63 Pages) ICHAUS

21 / 63 page

iC-TW8 16-BIT SIN/COS INTERPOLATOR

Pin Configuration Mode

Jan 9, 2013 Page PC9/15

www.ichaus.com

preliminar

Setting the Interpolation Factor

Configuration inputs C0 and C1 are used to select

the interpolation factor. Input C1 selects the desired

interpolation group I0, I1, or I2 and input C0 selects

the desired interpolation factor from within the se-

lected group. Choose the desired interpolation factor

from Table 2 and connect the appropriate resistors

to configuration input C0 (pin 30) according to Ta-

ble 1 to set the corresponding configuration level.

Level

Interp.

Group I0

Interp.

Group I1

Interp.

Group I2

x81921

x1600

x100001

x40962

x800

x50002

x2048

x400

x2500

x1024

x200

x1250

x512

x160

x1000

x256

x100

x500

x128

x80

x250

x64

x50

x125

x32

x40

x62.53

x16

x20

x25

x10

x12.53

x6.253

Table 2: Configuration Input C0

The interpolation factors shown in Table 2 are the

number or AB output cycles per Sin/Cos input cy-

cle. There are four times as many AB output edges

per Sin/Cos input cycle than as shown in the table.

Note that while the iC-TW8 is a true 16-bit interpo-

lator, x10000 is the maximum interpolation factor

available in pin configuration mode. Full 16-bit

(x16384) interpolation is available in serial configu-

ration mode.

1 This interpolation factor can only be used with heavy

filtering (C2 configuration levels 8–11) and lag

recovery enabled (C3 configuration levels 6–11).

2 This interpolation factor can only be used with normal

or heavy filtering (C2 configuration levels 4–11) and

lag recovery enabled (C3 configuration levels 6–11).

3 Z output is not synchronous with AB outputs when

using fractional interpolation factors.

Setting the Auto-Adaption Mode

Configuration input C1 is used to select the desired

auto-adaption mode and the interpolation group cor-

responding to the interpolation factor selected via

configuration input C0. Choose the desired auto-

adaption mode and interpolation group from Table 3

and connect the appropriate resistors to configura-

tion input C1 (pin 31) according to Table 1 to set the

corresponding configuration level.

Level

Auto-Adaption

Mode

Interpolation

Group

A3: Full analog

and digital auto-

adaption.

A2: Full digital

auto-adaption.

A1: Digital offset

and gain auto-

adaption.

A0: No auto-

adaption.

Table 3: Configuration Input C1

Three auto-adaption modes are available in pin con-

figuration mode. Mode A3 provides full analog and

digital auto-adaption. In this mode, the iC-TW8

continuously adjusts analog gain, analog offset,

digital offset, digital gain, and digital phase during

operation to maintain optimum performance and

lowest error and jitter.

Auto-adaption mode A2 provides full digital auto-

adaption and is the recommended mode for most

applications. In this mode, analog gain and offset

are fixed at the values established during device cal-

ibration (see Auto Calibration on page 12) and the

iC-TW8 continuously adjusts only the digital offset,

digital gain match, and digital phase during opera-

tion to maintain optimum performance and lowest

error and jitter.

Auto-adaption mode A1 is similar to mode A2 ex-

cept that digital phase is fixed at the value estab-

lished during device calibration and not adjusted

during operation.

In mode A0, auto-adaption is disabled and parame-

ter values are not adjusted from their initial calibra-

tion values during operation.

TW8 датащи(PDF) 21 Page - IC-Haus GmbH

TW8 датащи(HTML) 21 Page - IC-Haus GmbH

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

датащи скачать

ссылки URL