stlc3075 STMicroelectronics, stlc3075 Datasheet - Page 7

• Manufacturer Part Number: stlc3075
• Description: Integrated Pots Interface For Home Access Gateway And Wll
• Manufacturer: STMicroelectronics

STLC3075
3
3.1
Functional description
The STLC3075 is a device specifically developed for WLL VoIP and ISDN-TA applications. It
is based on a SLIC core, on purpose optimized for these applications, with the addition of a
DC/DC converter controller to meet the WLL and ISDN-TA design requirements.
The SLIC performs the standard feeding, signalling and transmission functions.
STLC3075 can be set in three different operating modes via the D0, D1, D2 pins of the
control logic interface (0 to 3.3V logic levels). The loop status is carried out on the DET pin
(active low).
The DET pin is an open drain output to allow easy interfacing with both 3.3V and 5V logic
levels.
The four possible SLIC’s operating modes are:
Table 2
Table 2.
DC/DC converter
The DC/DC converter controller drives an external power MOS transistor N-Ch plus
transformer (Flyback configuration) or P-Ch plus inductor (Buckboost configuration), in order
to generate the negative battery voltage needed for the device operation.
The DC/DC converter controller is synchronized with an external CLK (125kHz typ.) or with
an internal clock generated when the pin CLK is connected to CVCC. One R
to PGND supply (Flyback) or to V
input peak current.
This feature is implemented in order to avoid overload on V
transient (ex. ring trip detection). The 110m typical value guarantees an average current
consumption from V
guarantees an average current consumption from V
PD
0
1
1
1
1
1
1
–
–
–
–
shows how to set the different SLIC operating modes.
Power down
High impedance feeding (HI-Z)
Active
Ringing
D0
0
0
0
0
1
1
1
SLIC operating modes
D1
0
0
1
1
1
1
0
POS
< 700mA for buckboost configuration. The 220m typical value
0/1
D2
X
X
0
1
0
1
Power down
H.I. feeding (HI-Z)
Active normal polarity
Active reverse polarity
Active TTX injection (N.P.)
Active TTX injection (R.P.)
Ring (D2 bit toggles @ fring)
POS
supply (Buckboost) allows to fix the maximum allowed
POS
Operating mode
< 800mA for flyback configuration.
POS
supply in case of line
Functional description
SENSE
in series
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