Intersil Corporation HC5517 Datasheet

HC5517

Data Sheet July 1998 File Number

3 REN Ringing SLIC For ISDN Modem/TA
and WLL

he HC5517 is a ringing SLIC designed to accommodate a wide
variety of local loop applications. The various applications
include, basic POTS lines with ans w ering machines and fax
capabilities, ISDN networks, wireless local loop, and h ybrid
fiber coax (HFC) terminals. The HC5517 provides a high
degreeofflexibilitywith open circuit tip to ring DC voltages,user
defined ringing waveforms(sinusoidal to square wave),ring trip
detection thresholds and loop current limits that can be tailored
for many applications. Additional f eatures of the HC5517 are
complex impedance matching, pulse metering and transhybrid
balance. The HC5517 is designed for use in systems where a
separate ring generator is not economically feasible.

The device is manufacturedin a high voltage Dielectric Isolation
(DI) process with an operating voltage range from -16V, for off­hook operation and -80V for ring signal injection. The DI
process provides substrate latch up immunity, resulting in a
robust system design. Together with a secondary protection
diode bridge and “feed” resistors, the device will withstand
1000V lightning induced surges, in a plastic package.

A thermal shutdown with an alarm output and line fault
protection are also included for operation in harsh
environments.

Ordering Information

PART

NUMBER

HC5517IM -40 to 85 28 Ld PLCC N28.45
HC5517CM 0 to 75 28 Ld PLCC N28.45
HC5517IB -40 to 85 28 SOIC M28.3
HC5517CB 0 to 75 28 SOIC M28.3

TEMP.RANGE

(oC) PACKAGE PKG. NO.

4147.2

Features

• Thru-SLIC Open Circuit Ringing Voltage up to
77V

PEAK

/54V

, 3 REN Capability at 44V

RMS

RMS

• Sinusoidal Ringing Capability

• DI Process Provides Substrate Latch Up Immunity when
Driving Inductive Ringers

• Adjustable On-Hook Voltage for Fax and Answering
Machine Compatibility

• Resistive and Complex Impedance Matching

• Programmable Loop Current Limit

• Switch Hook and Adjustable Ring Trip Detection

• Pulse Metering Capability

• Single Low Voltage Positive Supply (+5V)

Applications

• Solid State Line Interface Circuit for Wireless Local Loop,
Hybrid Fiber Coax, Set Top Box, Voice/Data Modems

• Related Literature

- AN9606, Operation of the HC5517 Evaluation Board

- AN9607, Impedance Matching Design Equations

- AN9628, AC Voltage Gain

- AN9608, Implementing Pulse Metering

- AN9636, Implementing an Analog Port for ISDN Using

the HC5517

- AN549, The HC-5502S/4X Telephone Subscriber Line

Interface Circuits (SLIC)

Block Diagram

RING SENSE 1
RING SENSE 2

TIP FEED

TIP SENSE

RING FEED

V

REF

RTI

V

BAT

V

CC

AGND
BGND

60

2-WIRE

INTERFACE

BIAS

V

4-WIRE

INTERFACE

LOOP CURRENT

DETECTOR

FAULT

DETECTOR

CURRENT

LIMIT

RING TRIP

DETECTOR

IIL LOGIC INTERFACE

F1 F0 RS

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

TST RDI

http://www.intersil.com or 407-727-9207 | Copyright © Intersil Corporation 1999

-

+

RELAY

DRIVER

RX

V

TX

V

RING

- IN 1

OUT 1

SHD
ALM

I

LMT

RTD
RDO

HC5517

Absolute Maximum Ratings T

Maximum Supply Voltages

(VCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.5V to +7V

(VCC)-(V

Relay Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.5V to +15V

) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90V

BAT

Operating Conditions

Operating Temperature Range

HC5517IM, HC5517IB . . . . . . . . . . . . . . . . . . . . . . -40oC to 85oC

HC5517CM, HC5517CB . . . . . . . . . . . . . . . . . . . . . . 0oC to 75oC

Relay Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+5V to +12V

Positive Power Supply (VCC). . . . . . . . . . . . . . . . . . . . . . . +5V ±5%

Negative Power Supply (V

CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operationofthe
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.

NOTES:

1. θJA is measured with the component mounted on an evaluation PC board in free air.

2. All grounds (AGND, BGND) must be applied before VCCor V
to run separate grounds off a line card, the AG must be applied first.

) . . . . . . . . . . . . . . . . . . .-16V to -80V

BAT

Electrical Specifications Unless Otherwise Specified, Typical Parameters are at T

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

=25oC Thermal Information

A

Thermal Resistance (Typical, Note 1) θJA(oC/W)

PLCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

SOIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Maximum Junction Temperature Plastic . . . . . . . . . . . . . . . . .150oC

Maximum Storage Temperature Range. . . . . . . . . . -65oC to 150oC

Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . .300oC

(SOIC, PLCC - Lead Tips Only)

Die Characteristics

Transistor Count. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224

Diode Count. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28

Die Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174 x 120

Substrate Potential. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .V

Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bipolar-DI

ESD (Human Body Model) . . . . . . . . . . . . . . . . . . . . . . . . . . . .500V

. Failure to do so may result in premature failure of the part. If a user wishes

BAT

Operating TemperatureRange, V
at 600Ω 2-Wire terminating impedance.

= -24V,VCC= +5V,AGND = BGND = 0V. All AC Parametersare specified

BAT

= 25oC, Min-Max Parameters are over

A

BAT

RINGING TRANSMISSION PARAMETERS

Input Impedance (Note 3) - 5.4 - kΩ

V

RING

4-Wire to 2-Wire Gain V

AC TRANSMISSION PARAMETERS

RX Input Impedance 300Hz to 3.4kHz (Note 3) - 108 - kΩ
TX Output Impedance 300Hz to 3.4kHz (Note 3) - - 20 Ω
4-Wire Input Overload Level 300Hz to 3.4kHz R

2-Wire Return Loss Matched for 600Ω (Note 3)

SRL LO 26 35 - dB
ERL 30 40 - dB
SRL HI 30 40 - dB

2-Wire Longitudinal to Metallic Balance
Off Hook

4-Wire Longitudinal Balance Off Hook 300Hz to 3400Hz (Note 3) 50 55 - dB
Low Frequency Longitudinal Balance I
Longitudinal Current Capability I
Insertion Loss 0dBm at 1kHz, Referenced 600Ω

2-Wire/4-Wire (Includes external transhybrid
amplifier with a gain of 3)

to Vt-r (Note 3) - 40 - V/V

RING

= 1200Ω, 600Ω Reference

(Note 3)

Per ANSI/IEEE STD 455-1976 (Note 3)
300Hz to 3400Hz

= 40mA TA = 25oC (Note 3) - 10 23 dBrnC

LINE

= 40mA TA = 25oC (Note 3) - - 40 mA

LINE

L

+1.0 - - V

58 63 - dB

- ±0.05 ±0.2 dB

PEAK

RMS

4-Wire/2-Wire - ±0.05 ±0.2 dB
4-Wire/4-Wire (Includes external transhybrid

amplifier with a gain of 3)

--±0.25 dB

61

HC5517

Electrical Specifications Unless Otherwise Specified, Typical Parameters are at T

Operating TemperatureRange, V

= -24V,VCC= +5V,AGND = BGND = 0V. All AC Parametersare specified

BAT

= 25oC, Min-Max Parameters are over

A

at 600Ω 2-Wire terminating impedance. (Continued)

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Frequency Response 300Hz to 3400Hz (Note 3) Referenced to

- ±0.02 ±0.06 dB

Absolute Level at 1kHz, 0dBm Referenced 600Ω

Level Linearity Referenced to -10dBm (Note 3)

2-Wire to 4-Wire and 4-Wire to 2-Wire +3 to -40dBm - - ±0.08 dB

-40 to -50dBm - - ±0.12 dB

-50 to -55dBm - - ±0.3 dB

Absolute Delay (Note 3)

2-Wire/4-Wire 300Hz to 3400Hz - - 1.0 µs
4-Wire/2-Wire 300Hz to 3400Hz - - 1.0 µs

4-Wire/4-Wire 300Hz to 3400Hz - 0.95 1.5 µs
Transhybrid Loss V
Total Harmonic Distortion

2-Wire/4-Wire, 4-Wire/2-Wire, 4-Wire/4-Wire
Idle Channel Noise

2-Wire and 4-Wire

= 1V

IN

Reference Level 0dBm at 600Ω
300Hz to 3400Hz (Note 3)

(Note 3)
C-Message

at 1kH (Notes 3, 4) 30 40 dB

P-P

- - -50 dB

- 3 - dBrnC

Psophometric (Note 3) - -87 - dBmp

Power Supply Rejection Ratio (Note 3)

to 2-Wire 20 40 - dB

V

CC

to 4-Wire 20 40 - dB

V

CC

to 2-Wire 20 40 - dB

V

BAT

to 4-Wire 20 50 - dB

V

BAT

to 2-Wire (Note 3)

V

CC

to 4-Wire 20 28 - dB

V

CC

to 2-Wire 20 50 - dB

V

BAT

to 4-Wire 20 50 - dB

V

BAT

30Hz to 200Hz, RL = 600Ω

30 40 - dB

200Hz to 16kHz, RL = 600Ω

DC PARAMETERS

Loop Current Programming

Limit Range 20

-60mA

(Note 5)

Accuracy 10 - - %
Loop Current During Power Denial R

= 200Ω - ±4 ±7mA

L

Fault Currents

TIP to Ground (Note 3) -30-mA

RING to Ground - 120 - mA

TIP and RING to Ground (Note 3) - 150 - mA
Switch Hook Detection Threshold -1215mA
Ring Trip Comparator Voltage Threshold -0.28 -0.24 -0.22 V
Thermal

ALARM Output (Note 3) Safe Operating Die Temperature Exceeded 140 - 160

o

C

62

HC5517

Electrical Specifications Unless Otherwise Specified, Typical Parameters are at T

Operating TemperatureRange, V

= -24V,VCC= +5V,AGND = BGND = 0V. All AC Parametersare specified

BAT

= 25oC, Min-Max Parameters are over

A

at 600Ω 2-Wire terminating impedance. (Continued)

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Dial Pulse Distortion (Note 3) - 0.1 0.5 ms
Uncommitted Relay Driver

On Voltage V

OL

IOL (RDO) = 30mA - 0.2 0.5 V

Off Leakage Current - ±10 ±100 µA
TTL/CMOS Logic Inputs (F0, F1, RS,

Logic ‘0’ V

Logic ‘1’ V
Input Current (F0, F1, RS,
Input Current (F0, F1, RS,

IL
IH

TST, RDI) IIH, 0V ≤ VIN≤ 5V - - -1 µA
TST, RDI) IIL, 0V ≤ VIN≤ 5V - - -100 µA

TST, RDI)

0 - 0.8 V

2.0 - 5.5 V

Logic Outputs

Logic ‘0’ V

Logic ‘1’ V

OL
OH

Power Dissipation On Hook V

Power Dissipation Off Hook V

I

= 800µA - 0.1 0.5 V

LOAD

I

= 40µA 2.7 - - V

LOAD

CC

V

CC
CC

= +5V, V
= +5V, V
= +5V, V

= -80V, R

BAT

= -48V, R

BAT

= -24V, R

BAT

= ∞ - 300 - mW

LOOP

= ∞ - 150 - mW

LOOP
LOOP

= 600Ω,

- 280 - mW

IL = 25mA

I

CC

I

BAT

VCC = +5V, V

= +5V, V

V

CC

= +5V, V

V

CC

= -80V, R

BAT

= -48V, R

BAT

= -24V, R

BAT

VCC = +5V, VB- = -80V, R

= +5V, VB- = -48V, R

V

CC

= +5V, VB- = -24V, R

V

CC

= ∞ -36mA

LOOP

= ∞ -25mA

LOOP

= ∞ - 1.9 4 mA

LOOP

= ∞ - 3.6 7 mA

LOOP

= ∞ - 2.6 6 mA

LOOP

= ∞ - 1.8 4 mA

LOOP

UNCOMMITTED OP AMP PARAMETERS

Input Offset Voltage - ±5-mV
Input Offset Current - ±10 - nA
Differential Input Resistance (Note 3) - 1 - MΩ
Output Voltage Swing (Note 3) R

= 10kΩ - ±3-V

L

P-P

Small Signal GBW (Note 3) - 1 - MHz

NOTES:

3. These parameters are controlled by design or process parameters and are not directly tested. These parameters are characterized upon initial
design release, upon design changes which would affect these characteristics, and at intervals to assure product quality and specification com­pliance.

4. For transhybrid circuit as shown in Figure 10.

5. Application limitation based on maximum switch hook detect limit and metallic currents. Not a part limitation.

63

Functional Diagram

HC5517

PLCC/SOIC

TF

TIP

SENSE

RING

SENSE 1

RING

SENSE 2

RF

R

TF

25

14

15

16

26

-

+

100K
100K
100K

100K

R
R
R
R

4.5K

4.5K

RF

2R

-

+

2R

25K

-

+

25K

90K
90K

-

+

VRX
R
R

R/2

R/20

TA

RA

90K

OUT 1

17 12

+2V

VB/2

REF

SHD

RTD

-

+

-IN 1

OP AMP

V

RING

13 24 19 2

FAULT

DET

GM

V

­+

TX

THERM

LTD

RF2

V

CC

BIAS

NETWORK

SH

TSD

GK

RFC

AGND

IIL LOGIC INTERFACE

1

22

BGND

27

V

BAT

4

F1

5

F0

6

RS

9

TST

7

SHD

8

RTD

10

ALM

21

RDO

R = 108kΩ

V

REF

3

18

HC5517 TRUTH TABLE

F1 F0 ACTION

0 0 Loop power Denial Active
0 1 Power Down Latch RESET
0 1 Power on RESET
10
1 1 Normal Loop feed

Over Voltage Protection and Longitudinal Current
Protection

The SLIC device, in conjunction with an external protection
bridge, will withstand high voltage lightning surges and
power line crosses.

High voltage surge conditions are as specified in Table 1.
The SLIC will withstand longitudinal currents up to a

maximum or 30mA

RMS

, 15mA

per leg, without any

RMS

performance degradation

.

28

RTINU ILMT

RD Active

PARAMETER

Longitudinal
Surge

Metallic Surge 10µs Rise/

T/GND 10µs Rise/
R/GND
50/60Hz Current

T/GND 11 Cycles 700 (Plastic) V
R/GND Limited to

11

TABLE 1.

TEST

CONDITION

10µs Rise/
1000µs Fall

1000µs Fall

1000µs Fall

10A

RMS

20

RDI

PERFORMANCE

(MAX) UNITS

±1000 (Plastic) V

±1000 (Plastic) V

±1000 (Plastic)

PEAK

PEAK

PEAK

RMS

64

HC5517

Circuit Operation and Design Information

The HC5517 is a voltage feed current sense Subscriber Line
Interface Circuit (SLIC). This means that for long loop appli-

cations the SLIC provides a constant voltage to the tip and
ring terminals while sensing the tip to ring current. For short
loops, where the loop current limit is exceeded, the tip to ring
voltage decreases as a function of loop resistance.

The following discussion separates the SLIC’s operation into
its DC and AC path, then follows up with additional circuit
design and application information.

DC Operation of Tip and Ring Amplifiers

SLIC in the Active Mode

The tip and ring amplifiers are voltage feedback op amps
that are connected to generate a differential output (e.g. if tip
sources 20mA then ring sinks 20mA). Figure 1 shows the
connection of the tip and ring amplifiers. The tip DC voltage
is set by an internal +2V reference, resulting in -4V at the
output. The ring DC voltage is set by the tip DC output volt­age and an internal V
at the output. (See Equation 1, Equation 2 and Equation 3.)

V

TIPFEEDVC

V

RINGFEEDVD

==

/2 reference, resulting in V

BAT

R



-----------

2V–



R2⁄

V

BAT

-------------- -

2

4V–== =

R



1



V

--- -+

–

R

TIPFEED

R



--- -



R

BAT

(EQ. 1)

(EQ. 2)

+4V

Current Limit

The tip feed to ring feed voltage (Equation 1 minus
Equation 3) is equal to the battery voltage minus 8V. Thus,
with a 48 (24) volt battery and a 600Ω loop resistance,
including the feed resistors, the loop current is 66.6mA
(26.6mA). On short loops the line resistance often
approaches zero and the need exists to control the
maximum DC loop current.

Current limiting is achieved by a feedback network (Figure 1)
that modifies the ring feed voltage (V

) as a function of the

D

loop current. The output of the Transversal Amplifier (TA) has
a DC voltage that is directly proportional to the loop current.
This voltage is scaled by R

and R28. The scaled voltage is

10

the input to a transconductance amplifier (GM) that
compares it to an internal reference level. When the scaled
voltage exceeds the internal reference level, the
transconductance amplifier sources current. This current
charges C
voltage (V
effectively reduces the tip feed to ring feed voltage (V

in the positive direction causing the ring feed

16

) to approach the tip feed voltage (VC). This

D

T-R

and holds the maximum loop current constant.
The maximum loop current is programed by resistors R

10

and R28as shown in Equation 4 (Note: R10is typically
100kΩ).

I

LIMIT

0.6()R10R28+()

---------------------------------------------=

()

200xR

28

(EQ. 4)

),

V

RINGFEEDVDVBAT

R

TIP

RING

V

, V

OUT1

GROUNDED FOR
DC ANALYSIS

R

11

R

RX

13

R

14

12

4+==

R

TIP FEED

-

+

-

V

C

+

TRANSVERSAL
AMP

90kΩ 90kΩ

RING FEED

-

+

+

V

D

-

(EQ. 3)

V

RX

R

R

OUT1

R/20

V

RING

R/2

INTERNAL

+

-

+2V REF

TA

-

+

R

10

R

28

90kΩ

C

16

RF2

V

TX

GM

-

+

V

-

BAT

+

2

FIGURE 1. OPERATION OF THE TIP AND RING AMPLIFIERS

0

V

TIP FEED

-5

-10

-15

-20

TIP AND RING VOLTAGE (V)

-25

CURRENT LIMIT

REGION I

0

FIGURE 2. V

Figure 2 illustrates the relationship between V

= -4V

= 25mA

LOOP

250

LOOP RESISTANCE (Ω)

vs RL(V

T-R

CONSTANT VOLTAGE

V

RING FEED

500 750

= -24V, I

BAT

LIMIT

REGION

= 25mA)

T-R

= -20V

∞

and the
loop resistance. The conditions are shown for a battery volt­age of -24V and the loop current limit set to 25mA. For a infi­nite loop resistance both tip feed and ring feed are at -4V
and -20V respectively. When the loop resistance decreases
from infinity to about 640Ω the loop current (obeying Ohm’s
Law) increases from 0mA to the set loop current limit. As the
loop resistance continues to decrease, the ring feed voltage
approaches the tip feed voltage as a function of the pro­gramed loop current limit (Equation 4).

65