| Performs all battery, overvoltage, ringing, supervision, coding, hybrid and test (BORSCHT) functions |
| Internal balanced ringing to 150 VPK |
| External bulk ringer support |
| Low standby power consumption: <20 mW per channel |
| 2.5 Vrms pulse metering |
| Software programmable parameters: |
| Ringing frequency, amplitude, cadence, and waveshape |
| Two-wire ac impedance |
| Transhybrid balance |
| Dc current loop feed (16–55 mA) |
| Loop closure and ring trip thresholds |
| Ground key detect threshold |
| Automatic switching of up to three battery supplies |
| On-hook transmission |
| Loop or ground start operation |
| Smooth polarity reversal |
| Dual tone generators |
| A-Law/µ-Law companding, linear PCM |
