Si32172/3/5

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

27

Rev. 1.0 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • August 31, 2021

5. FXS Features

5.1. DC Feed Characteristics

ProSLIC internal linefeed circuitry provides completely programmable dc feed characteristics.

When in the active state, the ProSLIC operates in one of three dc linefeed operating regions: a constant-voltage

region, a constant-current region, or a resistive region, as shown in Figure 14. The constant-voltage region has a

low resistance, typically 160

. The constant-current region approximates infinite resistance.

Figure 14. Dual ProSLIC DC Feed Characteristics

5.2. Linefeed Operating States

The linefeed interface includes eight different register-programmable operating states as listed in Table 16. The

Open state is the default condition in the absence of any preloaded register settings. The device may also

automatically enter the open state in the event of a linefeed fault condition.

5.3. Line Voltage and Current Monitoring

The ProSLIC continuously monitors the TIP, RING, and battery voltages and currents via an on-chip ADC and

stores the resulting values in individual RAM locations. Additionally, the loop voltage (VTIP–VRING), loop current,

and longitudinal current values are calculated based on the TIP and RING measurements and are stored in unique

register locations for further processing. The ADC updates all registers at a rate of 2 kHz or greater.

ILOOP (mA)

I_RFEED

VTR(V)

I_ILIM

I_VLIM

Resistive Region

Constant V Region

V_VLIM

V_RFEED

V_ILIM