HC55121IBZ Intersil, HC55121IBZ Datasheet - Page 29
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HC55121IBZ
Manufacturer Part Number
HC55121IBZ
Description
Manufacturer
Intersil
Datasheet
1.HC55121IBZ.pdf
(36 pages)
Specifications of HC55121IBZ
Number Of Channels
1
On-hook Transmission
Yes
Polarity Reversal
Yes
On-chip Ring Relay Driver
Yes
Longitudinal Balanced
53
Operating Supply Voltage (typ)
5V
Operating Temp Range
-40C to 85C
Loop Current Limit
30mA
Operating Temperature Classification
Industrial
Pin Count
28
Mounting
Surface Mount
Operating Current
2.7mA
Operating Supply Voltage (max)
5.25V
Operating Supply Voltage (min)
4.75V
Lead Free Status / RoHS Status
Compliant
Pinouts - 28 Lead SOIC Packages
Pin Descriptions
PLCC
PIN
28
1
2
3
4
5
6
7
CRT_REV_LVM
PLCC
RDC_RAC
RDC_RAC
PIN
32
1
2
3
4
5
6
7
BGND
BGND
RRLY
RRLY
RING
RING
CDC
CDC
VBH
VBH
PTG
VBL
CRT
PTG
VBL
HC55120, HC55121, HC55130, HC55140, HC55142, HC55143, HC55150
TIP
TIP
CH
DR
CH
DR
DT
DT
ZT
ZT
SOIC
PIN
28
2
3
4
1
5
6
7
10
11
12
13
14
10
11
12
13
14
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
(28 LEAD SOIC)
(28 LEAD SOIC)
TOP VIEW
TOP VIEW
HC55130
HC55142
SYMBOL
29
BGND
RRLY
RING
PTG
CH
TIP
ZT
28
27
26
25
24
23
22
21
20
19
18
17
16
15
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 0.1µF.
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
AGND
VTX
NC
VRX
RSYNC
ILIM
ROH
RD
V
SHD
C1
C2
C3
NC
AGND
VTX
SPM
VRX
RSYNC_REV
ILIM
ROH
RD
V
SHD
C1
C2
C3
GKD_LVM
CC
CC
(Continued)
P
P
to ring wire of subscriber pair.
to tip wire of subscriber pair.
CRT_REV_LVM
CRT_REV_LVM
DESCRIPTION
RDC_RAC
RDC_RAC
BGND
BGND
RRLY
RRLY
RING
RING
CDC
CDC
PTG
VBH
PTG
VBH
VBL
VBL
TIP
TIP
CH
DR
CH
DR
DT
DT
ZT
ZT
10
11
12
13
14
10
11
12
13
14
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
(28 LEAD SOIC)
(28 LEAD SOIC)
TOP VIEW
TOP VIEW
HC55140
HC55150
28
27
26
25
24
23
22
21
20
19
18
17
16
15
28
27
26
25
24
23
22
21
20
19
18
17
16
15
AGND
VTX
NC
VRX
RSYNC_REV
ILIM
ROH
RD
V
SHD
C1
C2
C3
GKD_LVM
AGND
VTX
SPM
VRX
RSYNC_REV
ILIM
ROH
RD
V
SHD
C1
C2
C3
LVM
CC
CC
June 1, 2006
FN4659.13