MT8960/61/62/63/64/65/66/67
Logic Control Outputs SD0-5
These outputs are directly controlled by the logic
states of bits 0-5 in Register B. A logic low (GNDD)
in Register B causes the SD outputs to assume an
inactive state. A logic high (V
DD
) in Register B
causes the SD outputs to assume an active state
(see Table 3). SD0-2 switch between GNDD and V
DD
and may be used to control external logic or
transistor circuitry, for example, that employed on the
line card for performing such functions as relay drive
for application of ringing to line, message waiting
indication, etc.
SD3-5 are used primarily to drive external analog
circuitry. Examples may include the switching in or
out of gain sections or filter sections (eg., ring trip
filter) (Figure 7).
MT8962/63/66/67 provides all six SD outputs.
MT8960/61/64/65 each packaged in an 18-pin DIP
provide only four control outputs, SD0-3.
ISO
2
-CMOS
Telephone Set
2 Wire
Analog
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AA
AA
A
AA
AA
AA
PCM Highway
AA
AA
AA
AA
Supervision
AA
AA
AA
AA
Protection
AA
AA
AA
AA
AA
AA
AA
MT8960/61
AA
AA
Battery
AA
AA
MT8962/63
AA
AA
Feed
AA
AA
2W/4W
AA
AA
MT8964/65
AA
AA
Converter
AA
AA
Ringing
AA
AA
MT8966/67
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AA
AA
A
Figure 6 - Typical Line Termination
BITS 0-2
0
1
BIT 3
0
1
BITS 4,5
0
1
BIT 7
0
0
BIT 6
0
1
Normal operation.
LOGIC CONTROL OUTPUTS SD
0
-SD
2
Inactive state - logic low (GNDD).
Active state - logic high (V
DD
).
LOGIC CONTROL OUTPUT SD
3
Inactive state - High Impedance.
Active state - GNDA.
LOGIC CONTROL OUTPUTS SD
4
, SD
5
Inactive state - High Impedance.
Active state - GNDD.
CHIP TESTING CONTROLS
Transmit filter testing, i.e.:
Transmit filter input connected to V
X
input
Receive filter and Buffer disconnected from V
R
Receive filter testing, i.e.:
Receive filter input connected to V
X
input
Receive filter input disconnected from codec
Codec testing i.e.:
Codec analog input connected to V
X
Codec analog input disconnected from transmit filter output
Codec analog output connected to V
R
V
R
disconnected from receive filter output
Table 3. Control States - Register B
1
0
1
1
6-26