N681622YG Nuvoton Technology Corporation of America, N681622YG Datasheet - Page 44

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

Specifications of N681622YG

• Lead Free Status / RoHS Status: Supplier Unconfirmed

To maintain proper biasing of the external bipolar transistors the generated Ringing signal should stay between the
Ringing voltage rails (GNDA and V
excessive power dissipation in the external transistors will also occur. This can be prevented if V
such that:
An unbalanced ringing waveform can be generated by the N681386/87.
GMV:UBR[7] address (0x4D) to “1”. The Ringing signal is only applied to the RING lead and the TIP lead remains at
the programmed V
used to provide DC current for Ring Trip Detection (section 9.1.3.2.3). Positive V
point to move closer to ground. The internal unbalanced Ringing waveform is shown below.
The DC offset value should be set to less than half the ringing amplitude or the ringing signal will be clipped. Reverse
unbalanced Ringing waveform can be achieved by setting the GMV:UBR[7] address (0x4D) bit to 1 (the TIP lead
oscillates while the RING lead stays constant). In this mode, the polarity of V
Preliminary Datasheet Rev1.0
12.1.3.3.
12.1.3.2.4.
GM
voltage. The Ringing signal is programmed as described in section 9.1.3.1. A DC offset can be
INTERNAL UNBALANCED RINGING
V
BATH
BATH
LINEFEED CONSIDERATIONS DURING RINGING
). If the ringing signal approaches the rails the signal will distort. Furthermore
Figure 13: Unbalanced Ringing on TIP
>
2
×
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⎛
⎜
⎜ ⎜
⎝
A PEAK
+
Single Programmable Extended Codec/SLCC
V ROFF
⎞
⎟
⎟ ⎟
⎠
+
ROFF
V
CMR
This feature is enabled by setting
ROFF
must also be reversed.
values will cause the DC offset
N681386/87
BATH
is programmed
January 2010