le79r79 Zarlink Semiconductor, le79r79 Datasheet - Page 6

• Manufacturer Part Number: le79r79
• Description: Ringing Subscriber Line Interface Circuit
• Manufacturer: Zarlink Semiconductor

PIN DESCRIPTIONS
AGND/DGND
A(TIP)
B2EN
BGND
B(RING)
C3–C1
D1
D2
DET
E1
HPA
HPB
NC
RD
RDC
RDCR
RINGIN
RSGH
RSGL
RSN
RTRIP1
RTRIP2
RYE
RYOUT1
RYOUT2
VBAT1
VBAT2
VCC
VNEG
VTX
Pin Names
Ground
Output
Input
Ground
Output
Input
Input
Input
Output
Input
Capacitor
Capacitor
—
Resistor
Output
—
Input
Input
Input
Input
Input
Input
Output
Output
Output
Battery
Battery
Power
Power
Output
Type
Analog and digital ground
Output of A(TIP) power amplifier
V
compatible.
Battery (power) ground
Output of B(RING) power amplifier
Decoder. SLIC control pins. C3 is MSB and C1 is LSB. TTL compatible.
Relay1 Control. TTL compatible. Logic Low activates the Relay1 relay driver.
Relay2 Control. (Option) TTL compatible. Logic Low activates the Relay2 relay driver.
Hook switch detector. When enabled, a logic Low indicates that the selected detector is tripped. The logic
inputs C3–C1 and E1 select the detector. The output is open collector with a built-in 15 kΩ pull-up resistor.
Ground-Key Enable. (Option) A logic High selects the off-hook detector. A logic Low selects the ground-
key detector. TTL compatible.
High-Pass Filter. A(TIP) side of high-pass filter capacitor.
High-Pass Filter. B(RING) side of high-pass filter capacitor.
Not internally connected.
Detect Resistor. Detector threshold set and filter pin.
DC Feed Resistor. Connection point for the DC-feed current programming network. The other end of the
network connects to the receiver summing node (RSN). The sign of V
and positive for reverse polarity.
Connection point for feedback during ringing.
Ring Signal. Pin for ring signal input. Square-wave shaped by external RC filter. Requires 50% duty cycle.
CMOS-compatible input.
Saturation Guard High. Pin for resistor to adjust Open Circuit voltage when operating from V
Saturation Guard Low. Pin for resistor to adjust the anti-saturation cut-in voltage when operating from
both V
Receive Summing Node. The metallic current (both AC and DC) between A(TIP) and B(RING) is equal
to 1000 x the current into this pin. The networks that program receive gain, two-wire impedance, and feed
resistance all connect to this node.
Ring-Trip Detector. Ring-trip detector threshold set and filter pin.
Ring-Trip Detector. Ring-trip detector threshold offset (switch to V
nonringing state, this switch is open.
Common Emitter of RYOUT1/RYOUT2. Emitter output of RYOUT1 and RYOUT2. Normally connected to
relay ground.
Relay/Switch Driver. Open collector driver with emitter internally connected to RYE.
Relay/Switch Driver. (Option) Open collector driver with emitter internally connected to RYE.
Battery supply and connection to substrate.
Power supply to output amplifiers. Connect to off-hook battery through a diode.
Positive analog power supply
Negative analog power supply. This pin is the return for the internal V
Transmit Audio. This output is a 0.5066 gain version of the A(TIP) and B(RING) metallic AC voltage. VTX
also sources the two-wire input impedance programming network.
BAT2
Enable. Logic Low enables operation from V
BAT1 and
V
BAT2
Zarlink Semiconductor Inc.
.
6
Description
BAT2
. Logic High enables operation from V
BAT1
RDC
EE
). For power conservation in any
regulator.
is negative for normal polarity
BAT1
BAT1
.
. TTL