N681622YG Nuvoton Technology Corporation of America, N681622YG Datasheet - Page 39

• Manufacturer Part Number: N681622YG
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of N681622YG

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Oscillator 2 is also specifically used to generate the Ringing signal and is unavailable for other functions during
ringing. FSK generation does not utilize either one of the tone generation oscillators.
The N681386/87 supports balanced and unbalanced Ringing up to 90 VPK (5 REN up to 4 kft, 4REN up to 4.5 kft, 3
REN up to 8 kft). Oscillator 2 from the Tone Generation block is used to generate the Ringing waveform. However,
programming the waveform, sinusoidal or trapezoidal, involves some slight modifications to the procedures described
for Tone Generation. The active and inactive timers of oscillator 2 can be programmed between 0 seconds (timer
disabled) and 8 secs in 125us increments.
OS2RPD:O2RPD[7:0] address (0xAD).
All other oscillator operations are standard and follow the description in the tone generation section. Interrupts can
be enabled on the expiration of either timer, so that, for instance, Caller ID can be inserted between tones. Cadence
is activated when a non-zero value is programmed into both the active and inactive timers. In this case, these timers
effectively govern the transitions in and out of the Ringing state as described in Linefeed States of Operation in
Section 6.1.1.1.
When the Ring Automatic bit LAMC:RGA[1] address (0x43) is set, the oscillator is automatically enabled when the
Ringing state is entered and disabled when exited. If the Ring Automatic bit is enabled the transition from Ringing to
Active state (Forward or Reverse) occurs automatically upon Ring Trip Detect. The oscillator enable and ring enable
bits are automatically updated accordingly OSN:O2E[1] address (0xC0) and RMPC:R1EN[5] address (0xC1).
One-shot control of the oscillation can be achieved by controlling OSN:O2E[1] address (0xC0) together with the
active timer and the active timer interrupt for durations up to 8 seconds. For longer durations or for direct software
control of the oscillation, enabling the active timer by setting it to any non-zero value, while simultaneously disabling
the inactive timer completely, will put the oscillator under complete direct control of the OSN:O2E[1] address (0xC0)
bit. Zero crossing detect can be enabled by setting the OSN:O2ZC[3] address (0xC0). Setting this bit will ensure that
Preliminary Datasheet Rev1.0
12.1.3.2.
tone
tone
RING SIGNAL GENERATION
Figure 9: Zero Crossing for Tone Generation
cadence
cadence
Page 39 of 164
A Ring phase delay can also be programmed in the
Single Programmable Extended Codec/SLCC
tone
tone
N681386/87
cadence
cadence
January 2010