HC55120CM INTERSIL [Intersil Corporation], HC55120CM Datasheet - Page 29

• Manufacturer Part Number: HC55120CM
• Description: Low Power Universal SLIC Family
• Manufacturer: INTERSIL [Intersil Corporation]

Pinouts - 28 Lead SOIC Packages
Pin Descriptions
HC55120, HC55121, HC55130, HC55131, HC55140, HC55141, HC55142, HC55143, HC55150, HC55151
PLCC
PIN
28
10
11
12
13
14
1
2
3
4
5
6
7
8
9
-
CRT_REV_LVM
PLCC
RDC_RAC
PIN
32
10
11
12
13
14
15
1
2
3
4
5
6
7
8
9
BGND
RRLY
RING
CDC
VBH
PTG
VBL
TIP
CH
DR
DT
ZT
SOIC
PIN
28
10
14
11
12
13
2
3
4
1
5
6
7
8
9
-
10
11
12
13
14
1
2
3
4
5
6
7
8
9
(28 LEAD SOIC)
TOP VIEW
HC55142
4-29
RDC_RAC
CRT_REV
SYMBOL
BGND
RRLY
_LVM
RING
CDC
PTG
V
V
CH
TIP
DR
DT
C5
ZT
BH
BL
28
27
26
25
24
23
22
21
20
19
18
17
16
15
Programmable Transmit Gain - The 2-wire to 4-wire transmission gain is 0dB if this pin is left floating
and -6.02dB if tied to ground. The -6.02dB gain option is useful in systems where Pulse Metering is
used. See Figure 23.
Ring Relay Driver Output - The relay coil may be connected to a maximum of 14V.
AC/DC Separation Capacitor - CH is required to properly process the AC current from the DC loop
current. Recommended value 0.1 F.
2-Wire Impedance Matching Pin - Impedance matching of the 2-wire side is accomplished by placing
an impedance between the ZT pin and ground. See Equation 32.
Connects via protection resistor R
Battery ground.
Connects via protection resistor R
High Battery Supply (negative with respect to GND).
Low Battery Supply (negative with respect to GND, magnitude
Resistive Feed/Anti Clipping - Performs anti clipping function on constant current application and sets
the slope of the resistive feed curve for constant voltage applications.
Ring Trip, Soft Polarity Reversal and Line Voltage Measurement - A capacitor when placed between the
CRT_REV_LVM pin and +5V performs 3 mutually exclusive functions. When the SLIC is configured in the
Ringing mode it provides filtering of the ringing signal to prevent false detect. When the SLIC is transitioning
between the Forward Active State and Reverse Active State it provides Soft Polarity Reversal and performs
charge storage in the Line Voltage Measurement State. Recommended value 0.47 F.
Filter Capacitor- The CDC Capacitor removes the VF signals from the battery feed control loop.
Tip side of Ring Trip Detector - Ring trip detection is accomplished by connecting an external network
to a detector in the SLIC with inputs DT and DR. Ring trip occurs when the voltage on DT is more
negative than the voltage on DR.
Ring Side of Ring Trip Detector - Ring trip detection is accomplished by connecting an external
network to a detector in the SLIC with inputs DT and DR. Ring trip occurs when the voltage on DR is
more positive than the voltage on DT.
Activates Test Relay TRLY2.
AGND
VTX
SPM
VRX
RSYNC_REV
ILIM
ROH
RD
V
SHD
C1
C2
C3
GKD_LVM
CC
(Continued)
P
P
to ring wire of subscriber pair.
to tip wire of subscriber pair.
CRT_REV_LVM
DESCRIPTION
RDC_RAC
BGND
RRLY
RING
CDC
PTG
VBH
VBL
TIP
CH
DR
DT
ZT
10
11
12
13
14
1
2
3
4
5
6
7
8
9
(28 LEAD SOIC)
TOP VIEW
HC55150
V
BH
).
28
27
26
25
24
23
22
21
20
19
18
17
16
15
AGND
VTX
SPM
VRX
RSYNC_REV
ILIM
ROH
RD
V
SHD
C1
C2
C3
LVM
CC