E-STLC3075 STMicroelectronics, E-STLC3075 Datasheet - Page 15

• Manufacturer Part Number: E-STLC3075
• Manufacturer: STMicroelectronics

Specifications of E-STLC3075

• Number Of Channels: 1
• On-hook Transmission: Yes
• Polarity Reversal: Yes
• On-chip Ring Relay Driver: Yes
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Pin Count: 44
• Mounting: Surface Mount
• Operating Current: 55mA
• Operating Supply Voltage (max): 12V
• Lead Free Status / RoHS Status: Compliant

STLC3075
Once the ring trip is detected, the DET output is activated (logic level low). At this point the
card controller or a simple logic circuit stops the D2 toggling in order to effectively
disconnect the ring signal and then set the STLC3075 in the proper operating mode
(normally active).
Ring level in presence of more telephones in parallel
As already mentioned in the previous section, the maximum current that can be drawn from
the V
available at the self generated negative battery.
If for any reason the ringer load is too low, the self generated battery drops in order to keep
the power consumption to the fixed limit and consequently the ring voltage level is also
reduced.
In the typical buckboost configuration with R
limited to around 900 mApk, which correspond to an average current of 700 mA max. In this
condition the STLC3075 can drive up to 3REN with a ring frequency fr=25 Hz
(1REN = 1800 Ω + 1.0 µF, European standard).
In order to drive up to 5REN (1REN= 6930 Ω + 8 µF, US standard) it is necessary to modify
the external components as follows:
In flyback configuration the value of R
and USA standards. In order to drive 5REN (US standard) it is necessary to modify the
external component: R
POS
supply is controlled and limited via the external R
CREV = 15nF; RD = 2.2 kΩ; R
D
= 2.2 kΩ.
SENSE
SENSE
SENSE
= 220 mΩ guarantees to match both European
= 100 mΩ.
= 110 mΩ the peak current from V
SENSE
. This also limits the power
Functional description
POS
15/36
is