SI3233 datasheet(30/100 Pages) SILABS

30 / 100 page

Si3233

Preliminary Rev. 0.5

When the ringing state is invoked by writing

LF[2:0] = 100 (direct Register 64), the ProSLIC will go

into the ringing state and start the first ring. At the

expiration of RAT, the ProSLIC will turn off the ringing

waveform and will go to the on-hook transmission state.

At the expiration of RIT, ringing will again be initiated.

This process will continue as long as the two timers are

enabled and the Linefeed Control register is set to the

ringing state.

2.5.2. Sinusoidal Ringing

To configure the ProSLIC for sinusoidal ringing, the

frequency and amplitude are initialized by writing to the

following indirect registers: RCO, RNGX, and RNGY.

The equations for RCO, RNGX, RNGY are as follows:

where

and f = desired ringing frequency in hertz.

In selecting a ringing amplitude, the peak TIP-to-RING

ringing voltage must be greater than the selected on-

hook line voltage setting (VOC, direct Register 72). For

example, to generate a 70 VPK 20 Hz ringing signal, the

equations are as follows:

In addition, the user must select the sinusoidal ringing

waveform by writing TSWS = 0 (direct Register 34,

bit 0).

2.5.3. Trapezoidal Ringing

In addition to the sinusoidal ringing waveform, the

ProSLIC

supports

trapezoidal

ringing.

Figure 13

illustrates a trapezoidal ringing waveform with offset

VROFF.

Figure 13. Trapezoidal Ringing Waveform

To configure the ProSLIC for trapezoidal ringing, the

user should follow the same basic procedure as in the

Sinusoidal Ringing section, but using the following

equations:

RCO is a value which is added or subtracted from the

waveform to ramp the signal up or down in a linear

fashion. This value is a function of rise time, period, and

amplitude, where rise time and period are related

through the following equation for the crest factor of a

trapezoidal waveform.

Ringing amplitude

0 to 94.5 V

RNGX[15:0]

Indirect Register 8

Ringing initial phase

Sets initial phase for

sinewave and period

for

trapezoid

RNGY[15:0]

Indirect Register 9

Common Mode Bias Adjust During Ringing

0 to 22.5 V

VCMR[3:0]

Indirect Register 27

Note:

The ProSLIC uses registers that are both directly and indirectly mapped. A “direct” register is one that is mapped

directly. An “indirect” register is one that is accessed using the indirect access registers (direct registers 28 through

31).

Table 26. Registers for Ringing Generation (Continued)

RCO

coeff

()

coeff

πf

1000 Hz

-----------------------

⎝⎠

⎛⎞

cos

RNGX

---

1coeff

–

1coeff

------------------------

Desired VPK 0to94.5 V

()

96 V

------------------------------------------------------------------------

RNGY

coeff

π 20

1000 Hz

-----------------------

⎝⎠

⎛⎞

0.99211

cos

RCO

0.99211

()

32509

7EFDh

RNGX

---

0.00789

1.99211

---------------------

------

376

0177h

RNGY

time

VROFF

T=1/freq

tRISE

VTIP-RING

RNGY

--- Period

8000

RNGX

Desired VPK

96 V

-----------------------------------

()

RCO

2 RNGX

tRISE 8000

---------------------------------

SI3233 Datasheet(PDF) 30 Page - Silicon Laboratories

SI3233 Datasheet(HTML) 30 Page - Silicon Laboratories

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 93 94 95 96 97 98 99 100

Datasheet Download

Link URL