SI3061-X-KTR Просмотр технического описания (PDF) - Unspecified

Номер в каталоге

Компоненты Описание

производитель

SI3061-X-KTR

GLOBAL LINE-SIDE DAA FOR EMBEDDED SYSTEM-SIDE MODULE

Unspecified 

Si306x

and off-hook.

These registers can help determine the following:

When on-hook, detect if a line is connected.

When on-hook, detect if a parallel phone is off-hook.

When off-hook, detect if a parallel phone goes on or

off-hook.

Detect if enough loop current is available to operate.

When used in conjunction with the OPD bit, detect if

an overload condition exists (See "6.25. Overload

Detection" on page 26).

6.11.1. Line Voltage Measurement (Si3062, Si3063,

and Si3065 Only)

The Si3062, Si3063, and Si3065 devices report line

voltage with the LVS[7:0] bits (Register 29) in both on-

and off-hook states with a resolution of 1 V per bit. The

accuracy of these bits is approximately ±10%. Bits 0

through 6 of this register indicate the value of the line

voltage in 2s compliment format. Bit 7 of this register

indicates the polarity of the tip/ring voltage.

If the INTE bit (Register 2) and the POLM bit (Register

3) are set, a hardware interrupt is generated on the

AOUT/INT pin when bit 7 of the LVS register changes

state. The edge-triggered interrupt is cleared by writing

0 to the POLI bit (Register 4). The POLI bit is set each

time bit 7 of the LVS register changes state and must be

written to 0 to clear it.

The default state of the LVS register forces the LVS bits

to 0 when the line voltage is 3 V or less. The LVFD bit

(Register 31, bit 0) disables the force-to-zero function

and allows the LVS register to display non-zero values

of 3 V and below. This register might display

unpredictable values at line voltages between 0 to 2 V.

At 0 V, the LVS register displays all 0s.

6.11.2. Loop Current Measurement

When the DAA is off-hook, the LCS[4:0] bits measure

loop current in 3.3 mA/bit resolution. These bits enable

detection of another phone going off-hook by monitoring

the dc loop current. The line current sense transfer

function is shown in Figure 4 and detailed in Table 9.

The LCS and LCS2 bits report loop current down to the

minimum operating loop current for the DAA. Below this

threshold, the reported value of loop current is

unpredictable.

Overload

30

25

20

LCS

BITS

15

10

5

0

0 3.3 6.6 9.9 13.2 16.5 19.8 23.1 26.4 29.7 33 36.3 39.6 42.9 46.2 49.5 52.8 56.1 59.1 62.7 66 69.3 72.6 75.9 79.2 82.5 85.8 89.1 92.4 95.7 99 102.3

127

Loop Current (mA)

Figure 4. Typical Loop Current LCS Transfer Function

Preliminary Rev. 0.9

19

Share Link: