HC5549 Datasheet, PDF (13/13 Pages) Intersil Corporation – Low Power SLIC with Battery Switch

HC5549
Pin Description
PLCC SYMBOL
DESCRIPTION
1
TIP
TIP power amplifier output.
2
BGND Battery Ground - To be connected to zero potential. All loop current and longitudinal current flow from this ground.
Internally separate from AGND but it is recommended that it is connected to the same potential as AGND.
3
VBL
Low battery supply connection.
4
VBH
High battery supply connection.
5
SW+ Uncommitted switch positive terminal.
6
SW-
Uncommitted switch negative terminal.
7
SWC Switch control input. This TTL compatible input controls the uncommitted switch, with a logic “0” enabling the switch and
logic “1” disabling the switch.
8
F2
Mode control input - MSB. F2-F0 for the TTL compatible parallel control interface for controlling the various modes of
operation of the device.
9
F1
Mode control input.
10
F0
Mode control input.
11
E0
Detector Output Selection Input. This TTL input controls the multiplexing of the SHD (E0=1) and GKD (E0 =0) comparator
outputs to the DET output based upon the state at the F2-F0 pins.
12
DET
Detector Output - This TTL output provides hook status of the loop based upon the selected operating mode. The
detected output will either be switch hook, ground key or ring trip.
13
ALM
Thermal Shutdown Alarm. This pin signals the internal die temperature has exceeded safe operating temperature and
the device has been powered down automatically.
14
AGND Analog ground reference. This pin should be externally connected to BGND.
15
BSEL Selects between high and low battery, with a logic “1” selecting the high battery and logic “0” the low battery.
16
NC
This pin is a “no connect” and should remain floating proper device operation.
17
POL
Capacitor connected to this pin sets the polarity reversal slew rate.
18
VRB
Ringing Bias Input - Analog input to offset Tip output towards ground while in Ringing Mode.
19
VRX
Analog Receive Voltage - 4-wire analog audio input voltage. AC couples to codec.
20
VTX
Transmit output voltage - Output of impedance matching amplifier, AC couples to codec.
21
VFB
Feedback voltage for impedance matching. This voltage is scaled to accomplish impedance matching.
22
-IN
Impedance matching amplifier summing node.
23
VCC
Positive voltage power supply.
24
CDC
DC Biasing Filter Capacitor - Connects between this pin and VCC.
25
RTD
Ring trip filter network.
26
ILIM
Loop Current Limit programming resistor.
27
RD
Switch hook detection threshold programming resistor.
28
RING RING power amplifier output.
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