ETC AM79R241JC

Intelligent Access™ Voice Solutions
Am79R241
Intelligent Subscriber Line Interface Circuit (ISLIC™)
DISTINCTIVE CHARACTERISTICS
Monitor of two-wire interface voltages and
currents supports
— Voice transmission
— Through chip ring generation
Supports internal short loop and external ringing
+5 V and battery supplies
Dual battery operation for system power saving
— Automatic battery switching
— Programmable DC feed characteristics
— Independent of battery
— Current limited
— Selectable off-hook and ground-key thresholds
— Subscriber line diagnostics
— Leakage resistance
— Intelligent thermal management
Compatible with inexpensive protection
networks
— Accommodates low tolerance fuse resistors or
PTC thermistors
Metering capable
— Loop resistance
— 12 kHz and 16 kHz
— Line capacitance
— Smooth polarity reversal
— Bell capacitance
— Foreign voltage sensing
Tip-open state supports ground start signaling
Integrated test load switches/relay drivers
— Power cross and fault detection
BLOCK DIAGRAM
RSN
S ig n a l
T ra n s m is s io n
AD
V TX
SA
HPA
HPB
T w o-W ire
In te rfa c e
Lo n g itu din a l
C o n trol
G a in /L ev e l S h ift
V LB
SB
BD
A tte n u a to r
VSAB
V RE F
TM N
TM P
S ig na l
C o n ditio n in g
T h e rm a l
M anagem ent
C o n tro l
TM S
Fault
Meas
IM T
IL G
CREF
VBL
S w itc h
D riv e r
VBH
R e la y C on tro l
R2
R3
RYE
R e la y
D riv e rs
P1
In p u t D e c o d er a n d
C o n tro l R e g is te rs
P2
P3
LD
R1
R ela y
D riv e r 1
B G ND
GND
VCC
Publication# 080249 Rev: I
Issue Date: August 2000
Amendment: /0
TABLE OF CONTENTS
Distinctive Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Distinctive Characteristics of the Intelligent Access™ Voice Chipset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Connection Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Intelligent Access™ Voice Chipsets Linecard with Am79R241 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Linecard Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Operating Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Target Specifications (See note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Relay Driver Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Am79R241 Transmission Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Am79R241 Ringing Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Am79R241 Current-Limit Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Am79R241 Fault Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Timing Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Physical Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Revision Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2
Am79R241 Datasheet
The Am79R241, in combination with an ISLAC ™ device, implements the telephone line interface
function. This enables the design of a low cost, high performance, fully software programmable line
interface for multiple country applications worldwide. All AC, DC, and signaling parameters are fully
programmable via microprocessor or GCI interfaces on the ISLAC device. Additionally, the
Am79R241 device has integrated self-test and line-test capabilities to resolve faults to the line or
line circuit. The integrated test capability is crucial for remote applications where dedicated test
hardware is not cost effective.
DISTINCTIVE CHARACTERISTICS OF THE INTELLIGENT ACCESS™ VOICE CHIPSET
Performs all battery feed, ringing, signaling,
hybrid and test (BORSCHT) functions
Two chip solution supports high density, multichannel architecture
Single hardware design meets multiple country
requirements through software programming
of:
— Ringing waveform and frequency
— DC loop-feed characteristics and current-limit
— Off-hook debounce circuit
— Ground-key and ring-trip filters
— Off-hook detect de-bounce interval
— Transhybrid balance
— Transmit and receive gains
— Equalization
— Digital I/O pins
— A-law/µ-law and linear selection
Supports internal and external battery-backed
ringing
— Self-contained ringing generation and control
— Two-wire AC impedance
— Loop-supervision detection thresholds
Exceeds LSSGR and CCITT central office
requirements
Selectable PCM or GCI interface
— Supports most available master clock
frequencies from 512 kHz to 8.192 MHz
On-hook transmission
Power/service denial mode
Line-feed characteristics independent of battery
voltage
Only 5 V, 3.3 V and battery supplies needed
Low idle-power per line
Linear power-feed with intelligent powermanagement feature
Compatible with inexpensive protection
networks; Accommodates low-tolerance fuse
resistors while maintaining longitudinal balance
Monitors two-wire interface voltages and
currents for subscriber line diagnostics
Built-in voice-path test modes
Power-cross, fault, and foreign voltage
detection
Integrated line-test features
— Supports external ringing generator and ring
relay
— Leakage
— Ring relay operation synchronized to zero
crossings of ringing voltage and current
— Loop resistance
— Integrated ring-trip filter and software enabled
manual or automatic ring-trip mode
Supports metering generation with envelope
shaping
Smooth or abrupt polarity reversal
— Line and ringer capacitance
Adaptive transhybrid balance
— Continuous or adapt and freeze
Supports both loop-start and ground-start
signaling
Integrated self-test features
— Echo gain, distortion, and noise
0 to 70°C commercial operation
— –40°C to 85°C extended temperature range
available
Small physical size
Up to three relay drivers per ISLIC™ device
— Configurable as test load switches
Am79R241 Datasheet
3
BLOCK DIAGRAMS
Figure 1.
Example Four-Channel Linecard Block Diagram
4
7
A1
A m 7 9R 24 1
VCCD
LD1
B1
DGND1
VREF
A2
B2
A3
DGND2
7
RC
Networks
and
Protection
VCCA
A m 7 9R 24 1
LD2
4
IO1-IO4
AGND1
TSCA/G
AGND2
7
A m 7 9R 24 1
B3
3
A4
LD3
TSCB
P1-P3
DRA/DD
7
A m 7 9R 24 1
LD4
B4
RREF
Quad
ISLAC
Am79Q2243
DRB
DXB
DXA/DU
DCLK/S0
PCLK/FS
RSHB
BATH
MCLK
FS/DCL
RSLB
BATL
CS/RST
DIO/S1
INT
4
Am79R241 Datasheet
Figure 2.
Am79R241 Block Diagram
IA sense
AD
IA
RSN
IA
600
SA
A Amplifier
+
-
Fault
Meas.
+
HPA
-
+
TMS
VTX
VREF
BGND
+
HPB
Fault
Meas.
+
+
β = 0.01
-
SB
VREF
B Amplifier
IB
VSAB
IB sense
BD
VREF
IB
600
TMN
TMP
VREF
Thermal
Management
Control
Gain/Level Shift
To Power
Amplifiers
Thermal
Shutdown
VBH
IMT
IA
IB
−
600 600
ILG
Disconnect
Active Low Battery
Internal Ringing
Standby
IA
IB
+
600 600
Decoder
R2
RD1
RD2
R1
BGND
OHT Fixed Longitudinal
Voltage
Active High Battery
RYE
Reserved
VBL
Tip Open
High Neg
Batt Sel
R3
VLB
RD3
C1
C2
Control Register
CREF
C3
Demux
Power amplifiers positive supply
P1
P2
P3
Am79R241 Datasheet
LD
VCC
GND
5
ORDERING INFORMATION
Legerity standard products are available in several packages and operating ranges. The ordering number (valid
combination) is formed by a combination of the elements below. An ISLAC device must be used with this part.
Am79R241
J
C
TEMPERATURE RANGE
C= Commercial (0°C to +70°C)*
PACKAGE TYPE
J = 32-pin plastic leaded chip carrier (PL032)
DEVICE NAME/DESCRIPTION
Am79R241
Intelligent Subscriber Line Interface Circuit
Valid Combinations
Valid Combinations
Am79R241
JC
Valid combinations list configurations planned to
be supported in volume for this device. Consult
the local Legerity sales office to confirm
availability of specific valid combinations, and to
check on newly released valid combinations.
Note:
*Functionality of the device from 0°C to 70°C is guaranteed by production testing. Performance from –40°C to +85°C
is guaranteed by characterization and periodic sampling of production units.
6
Am79R241 Datasheet
BGND
2
1 32 31 30
AD
VCC
3
RSVD
VBH
4
BD
VBL
CONNECTION DIAGRAM
R1
5
29
SB
R2
6
28
SA
RYE
7
27
IMT
R3
8
26
ILG
25
CREF
Am79R241
32-Pin PLCC
TMS
9
TMP
10
24
RSVD
TMN
11
23
HPB
P1
12
22
HPA
P2
13
21
VTX
Am79R241 Datasheet
VREF
RSN
VLB
GND
VSAB
LD
P3
14 15 16 17 18 19 20
7
PIN DESCRIPTIONS
8
Pin
Pin Name
AD, BD
A, B Line Drivers
I/O
O
Description
Provide the currents to the A and B leads of the subscriber loop.
BGND
Ground
Ground return for high and low battery supplies.
CREF
+3.3 VDC
VCCD reference. It is the digital high logic supply rail, used by the ISLIC to ISLAC interface.
GND
Ground
HPA, HPB
High-Pass Filter
Capacitor
O
These pins connect to CHP, the external high-pass filter capacitor that separates the DC
loop-voltage from the voice transmission path.
Analog and digital ground return for VCC.
ILG
Longitudinal Current
Sense
O
ILG is proportional to the common-mode line current (IAD–IBD), except in disconnect mode,
where ILG is proportional to the current into grounded SB.
IMT
Metallic Current Sense
O
IMT is proportional to the differential line current (IAD + IBD), except in disconnect mode,
where IMT is proportional to the current into grounded SA. The Am79R241 indicates thermal
overload by pulling IMT to CREF.
LD
Register Load
I
The LD pin controls the input latch and responds to a 3-level input. When the LD pin is a
logic 1 ( >(Vref+0.3V) ), the logic levels on P1–P3 latch into the Am79R241 control register
bits that operate the mode-decoder. When the LD pin is a logic 0 ( <(Vref-0.3V) ), the logic
levels on P1–P3 latch into the Am79R241 control register bits that control the relay drivers
(RD1–RD3). When the LD pin level is at ~VREF, the control register contents are locked.
P1–P3
Control Bus
I
Inputs to the latch for the operating-mode decoder and the relay-drivers.
R1
Relay 1 Driver
O
Collector connection for relay 1 driver. Emitter internally connected to BGND.
R2
Relay 2 Driver
O
Collector connection for relay 2 driver. Emitter internally connected to RYE
R3
Relay 3 Driver
O
Collector connection for relay 3 driver. Emitter internally connected to RYE.
RSN
Receive Summing
Node
I
The metallic current between AD and BD is equal to 500 times the current into this pin.
Networks that program receive gain and two-wire impedance connect to this node. This input
is at a virtual potential of VREF.
RSVD
Reserved
RYE
Relay 2, 3 Common
Emitter
O
Emitter connection for R2 and R3. Normally connected to relay ground.
This is used during Legerity testing. In the application, this pin must be left floating.
SA, SB
A, B Lead Voltage
Sense
I
Sense the voltages on the line side of the fuse resistors at the A and B leads. External sense
resistors, RSA and RSB, protect these pins from lightning or power-cross.
TMP,
TMN, TMS
Thermal Management
External resistors connected from TMP to TMS and TMN to VBL to offload excess power
from the Am79R241.
VBH
Battery (Power)
Connection to high-battery supply used for ringing and long loops. Connects to the substrate.
When only a single battery is available, it connects to both VBH and VBL.
VBL
Battery (Power)
Connection to low-battery supply used for short loops. When only a single battery is available,
this pin can be connected to VBH.
VCC
+5 V Power Supply
VLB
Longitudinal Voltage
I
Sets the DC longitudinal voltage of the Am79R241. It is the reference for the longitudinal
control loop. When the VLB pin is greater than VREF, the Am79R241 sets the longitudinal
voltage to a voltage approximately half-way between the positive and negative power supply
battery rails. When the VLB pin is driven to levels between 0V and VREF, the longitudinal
voltage decreases linearly with the voltage on the VLB pin.
Positive supply for low voltage analog and digital circuits in the Am79R241.
VREF
1.4 V Analog
Reference
I
The ISLAC chip provides this voltage which is used by the Am79R241 for internal reference
purposes. All analog input and output signals interfacing to the ISLAC chip are referenced
to this pin.
VSAB
Loop Voltage
O
Scaled-down version of the voltage between the sense points SA and SB on this pin.
VTX
4-Wire Transmit Signal
O
The voltage between this pin and VREF is a scaled down version of the AC component of
the voltage sensed between the SA and SB pins. One end of the two-wire input impedance
programming network connects to VTX. The voltage at VTX swings positive and negative
with respect to VREF.
Am79R241 Datasheet
GENERAL DESCRIPTION
The Intelligent Accessä voice chipsets integrate all functions of the subscriber line. Two chip types
are used to implement the linecard; an Am79R241 device and an ISLAC device. These provide the
following basic functions:
1. The Am79R241: A high voltage, bipolar device that drives the subscriber line, maintains
longitudinal balance and senses line conditions.
2. The ISLAC device: A low voltage CMOS IC that provides conversion, control and DSP functions
for the Am79R241.
Complete schematics of linecards using the Intelligent Access voice chipsets for internal and external
ringing are shown in Figure 3 and Figure 4.
The Am79R241 uses reliable, bipolar technology to provide the power necessary to drive a wide
variety of subscriber lines. It can be programmed by the ISLAC device to operate in eight different
modes that control power consumption and signaling. This enables it to have full control over the
subscriber loop. The Am79R241 is designed to be used exclusively with the ISLAC devices. The
Am79R241 requires only +5 V power and the battery supplies for its operation.
The Am79R241 implements a linear loop-current feeding method with the enhancement of intelligent
Thermal Management. This limits the amount of power dissipated on the Am79R241 chip by
dissipating power in external resistors in a controlled manner.
Each ISLAC device contains high-performance circuits that provide A/D and D/A conversion for the
voice (codec), DC-feed and supervision signals. The ISLAC device contains a DSP core that handles
signaling, DC-feed, supervision and line diagnostics for all channels.
The DSP core selectively interfaces with three types of backplanes:
Standard PCM/MPI
Standard GCI
Modified GCI with a single analog line per GCI channel
The Intelligent Access voice chipset provides a complete software configurable solution to the
BORSCHT functions as well as complete programmable control over subscriber line DC-feed
characteristics, such as current limit and feed resistance. In addition, these chipsets provide system
level solutions for the loop supervisory functions and metering. In total, they provide a programmable
solution that can satisfy worldwide linecard requirements by software configuration.
Software programmed filter coefficients, DC-feed data and supervision data are easily calculated
with the WinSLACä software. This PC software is provided free of charge. It allows the designer to
enter a description of system requirements. WinSLAC then computes the necessary coefficients
and plots the predicted system results.
The Am79R241 interface unit inside the ISLAC device processes information regarding the line
voltages, loop currents and battery voltage levels. These inputs allow the ISLAC device to place
several key Am79R241 performance parameters under software control.
The main functions that can be observed and/or controlled through the ISLAC backplane interface
are:
DC-feed characteristics
Ground-key detection
Off-hook detection
Metering signal
Longitudinal operating point
Subscriber line voltage and currents
Ring-trip detection
Abrupt and smooth battery reversal
Am79R241 Datasheet
9
Subscriber line matching
Ringing generation
Sophisticated line and circuit tests
To accomplish these functions, the ISLIC device collects the following information and feeds it, in
analog form, to the ISLAC device:
The metallic (IMT) and longitudinal (ILG) loop currents
The AC (VTX) and DC (VSAB) loop voltage
The outputs supplied by the ISLAC device to the ISLIC device are then:
A voltage (VHLi) that provides control for the following high-level ISLIC device outputs:
— DC loop current
— Internal ringing signal
— 12 or 16 kHz metering signal
A low-level voltage proportional to the voice signal (VOUTi)
A voltage that controls longitudinal offset for test purposes (VLBi)
The ISLAC device performs the codec and filter functions associated with the four-wire section of
the subscriber line circuitry in a digital switch. These functions involve converting an analog voice
signal into digital PCM samples and converting digital PCM samples back into an analog signal.
During conversion, digital filters are used to band-limit the voice signals.
The user-programmable filters set the receive and transmit gain, perform the transhybrid balancing
function, permit adjustment of the two-wire termination impedance and provide frequency
attenuation adjustment (equalization) of the receive and transmit paths. Adaptive transhybrid
balancing is also included. All programmable digital filter coefficients can be calculated using
WinSLAC software. The PCM codes can be either 16-bit linear two’s-complement or 8-bit
companded A-law or µ-law.
Besides the codec functions, the Intelligent Access voice chipset provides all the sensing, feedback,
and clocking necessary to completely control ISLIC device functions with programmable parameters.
System-level parameters under programmable control include active loop current limits, feed
resistance, and feed mode voltages.
The ISLAC device supplies complete mode control to the ISLIC device using the control bus
(P1-P3) and tri-level load signal (LDi).
The Intelligent Access voice chipset provides extensive loop supervision capability including offhook, ring-trip and ground-key detection. Detection thresholds for these functions are programmable.
A programmable debounce timer is available that eliminates false detection due to contact bounce.
For subscriber line diagnostics, AC and DC line conditions can be monitored using built-in test tools.
Measured parameters can be compared to programmed threshold levels to set a pass/fail bit. The
user can choose to send the actual measurement data directly to a higher level processor by way
of the PCM voice channel. Both longitudinal and metallic resistance and capacitance can be
measured, which allows leakage resistance, line capacitance, and telephones to be identified.
10
Am79R241 Datasheet
INTELLIGENT ACCESS™ VOICE CHIPSETS LINECARD WITH Am79R241
Figure 3.
Internal Ringing Linecard Schematic
+5 V
VCC
RSAi
3.3 V
CREF
SA
RRXi
VOUTi
RSN
DGND
RHLai
A
RFAi
RHLbi
CHLbi
AD
VHLi
RHLci
U3
D1
RTi
RHLdi
CHLdi
AGND
VREF
CADi
VCCA
VSAB
CHPi
BATH
VSABi
VCC
+3.3VDC
VCCD
HPA
CS
DT1i
VTX
VINi
VLB
VLBi
IMT
VIMTi
HPB
D2
U4
CSSi
B
RFBi
BD
RSBi
SB
CBDi
TMS
RTEST
RMTi
U1
Am79R241
VREF
RMGPi
VILGi
ILG
DT2i***
U2
ISLAC
BACK
PLANE
TMP
RLGi
TMN
VREF
RMGLi
DHi
BATH
VREF
VBH
VREF
DLi
BATL
VBL
LD
LDi
SPB
P1
SLB
GND
CBATHi
CBATLi
P1
RSVD
P2
P2
P3
P3
BATL
RSLB
BATH
SHB
RSHB
RYE
IREF
R2
RREF
R3
* CSS required for > 2.2 Vrms metering
** Connections shown for one channel
*** DT2i diode is optional - should be connected
if there is a chance that this chip may be
replaced by the Am79R251 device. Otherwise,
it creates a short.
R1
BGND
RSVD
Am79R241 Datasheet
11
Figure 4.
External Ringing Linecard Schematic
RSAi
+5 V
3.3 V
VCC
SA
CREF
RRXi
VOUTi
RSN
RHLai
A
RFAi
1
8
RHLbi
CHLbi
AD
DGND
KRi(A)
AGND
VHLi
RHLci
CADi
6
7
RTi
U5
RHLdi
CHLdi
VREF
VCCA
VSABi
VSAB
2
BATH
DT1i
CHPi
HPA
VTX
VINi
VLB
VLBi
IMT
VIMTi
VCC
+3.3 VDC
VCCD
CS
HPB
CSSi
RFBi
B
KRi (B)
4
5
CBDi
BD
RSBi
RMTi
SB
TMS
RTES T
U1
Am79231
VREF
VILGi
ILG
U2
ISLAC
RMGPi
DT2i***
RLGi
BACK
PLANE
TMP
VREF
TMN
VREF
VREF
RMGLi
DHi
BATH
VBH
LDi
GND
DLi
BATL
VBL
CBATHi
LD
CBATLi
P1
P1
P2
P2
P3
P3
SPB
SLB
BATL
RSLB
RSVD2
SHB
IREF
R2H
RREF
R3H
R1
RGFDLi
KRi
+5 V
Ring Bus
BGND
RSVD
* CSS required for > 2.2 Vrms metering
** Connections shown for one channel
*** DT2i is optional - Should be present if there is a chance that
this chip may be replaced by the Am79R251 device. Otherwise,
it creates a short.
RSRBi
RSRC
12
BATH
RSHB
RYE
Am79R241 Datasheet
XSBi
XSC
LINECARD PARTS LIST
The following list defines the parts and part values required to meet target specification limits for
channel i of the linecard (i = 1, 2, 3, 4)..
Item
Type
U1
Am79R241
U2
Am79X22xx
U3, U4
B1100CC
U5
TISP61089A
D1, D2
Value
Tol.
Rating
ISLIC device
ISLAC device
100 V
TECCOR Battrax protector
Transient Voltage Suppresser, Power
Innovations
Diode
1A
100 V
DHi, DLi, DT1i, DT2i
Diode
100 mA
100 V
4
Comments
RFAi, RFBi
Resistor
50 Ω
2%
2W
RSAi, RSBi
Resistor
200 kΩ
2%
1/4 W
RTi
Resistor
80.6 kΩ
1%
1/10 W
RRXi
Resistor
100 kΩ
1%
1/10 W
RREF
Resistor
69.8 kΩ
1%
1/10 W
RMGLi, RMGPi
Resistor
1 kΩ
5%
1W
RSHB, RSLB
Resistor
750 kΩ
1%
1/8 W
RHLai
Resistor
40.2 kΩ
1%
1/10 W
50 ns
Fusible PTC protection resistors
Sense resistors
Current reference
Thermal management resistors
RHLbi
Resistor
4.32 kΩ
1%
1/10 W
RHLci
Resistor
2.87 kΩ
1%
1/10 W
RHLdi
Resistor
2.87 kΩ
1%
1/10 W
CHLbi
Capacitor
3.3 nF
10 %
10 V
Not Polarized
Ceramic
CHLdi
Capacitor
0.82 µF
10 %
10 V
RMTi
Resistor
3.01 kΩ
1%
1/8 W
RLGi
Resistor
6.04 kΩ
1%
1/8 W
RTEST
Resistor
2 kΩ
1%
1W
Capacitor
22 nF
10%
100 V
CBATHi, CBATLi
Capacitor
100 nF
20%
100 V
Ceramic
CHPi
Capacitor
22 nF
20%
100 V
Ceramic
CSi1
Capacitor
100 nF
20%
100 V
Protector speed up capacitor
Capacitor
56 pF
5%
100 V
Ceramic
1.2 W typ
CADi, CBDi
1
3
CSSi
Test board
Ceramic, not voltage sensitive
Components for External Ringing
RGFDi
Resistor
510 Ω
2%
2W
RSRBi, RSRc
Resistor
750 kΩ
2%
1/4 W
KRi
Relay
5 V Coil
Matched to within 0.2% for initial tolerance
and 0 to 70 ° C ambient temperature range.2
17 mW typ
DPDT
Notes:
1. Value can be adjusted to suit application.
2. Can be looser for relaxed ring-trip requirements.
3. Required for metering > 2.2 Vrms, otherwise may be omitted.
4. DT2i is optional - Should be put if there is a chance that this chip may be replaced by Am79R251.
Am79R241 Datasheet
13
ELECTRICAL CHARACTERISTICS
Power Dissipation
Loop resistance = 0 to ∞ unless otherwise noted (not including fuse resistors), 2 x 50 Ω fuse resistors,
BATL = –36 V, BATH = –90 V, VCC = +5 V. For power dissipation measurements, DC-feed conditions
are as follows:
ILA (Active mode current limit) = 25 mA (IRSN = 50 µA)
RFD (Feed resistance) = 500 Ω
VAS (Anti-sat activate voltage) = 10 V
VAPP (Apparent Battery Voltage) = 48 V
RMGL = RMGP (Thermal management resistors) = 1 kΩ
Description
Power Dissipation
Normal Polarity
Test Conditions
Max
55
70
On-Hook Standby
80
100
On-Hook Transmission
Fixed Longitudinal Voltage
ISLIC
175
215
On-Hook Active High Battery
ISLIC
340
400
Off-Hook Active Low Battery
RL = 294 Ω
ISLIC
TMG
700
200
800
VBH
VBL
VCC
0.4
0.1
3.0
0.7
VBH
VBL
VCC
0.75
0
3.1
1.1
VBH
VBL
VCC
1.85
0
5
2.5
VBH
VBL
VCC
3.6
0
7.3
4.5
VBH
VBL
VCC
0.9
26.9
7.5
2.0
On-Hook Standby
On-Hook Transmission
Fixed Longitudinal Voltage
On-Hook Active High Battery
Off-Hook Active Low Battery
RL = 294 Ω
14
Typ
On-Hook Disconnect
On-Hook Disconnect
Power Supply Currents
Min
Am79R241 Datasheet
Unit
mW
3.5
3.5
mA
6
8.0
10
Thermal Resistance
The junction to air thermal resistance of the Am79R241 in a 32-pin, PLCC package is 45°C/W. The
typical junction to case thermal resistance is 14°C/W. Measured under free air convection conditions
and without external heatsinking.
Absolute Maximum Ratings
Storage temperature
–55 to +150°C
Ambient temperature, under bias
–40 to +85°C
VCC with respect to GND
–0.4 to +7 V
VBH, VBL with respect to GND2
+0.4 to –104 V
BGND with respect to GND
–3 to +3 V
Voltage on relay outputs
+7 V
AD or BD to BGND:
Continuous
VBH – 1 to BGND + 1
10 ms (F = 0.1 Hz)
VBH – 5 to BGND + 5
1 µs (F = 0.1 Hz)
VBH – 10 to BGND + 10
250 ns (F = 0.1 Hz)
VBH – 15 to BGND + 15
Current into SA or SB: 10 µs rise to Ipeak; 1000 µs fall to 0.5 Ipeak;
2000 µs fall to I =0
Ipeak = ±5 mA
Current into SA or SB: 2 µs rise to Ipeak; 10 µs fall to 0.5 Ipeak; 20 µs fall to I = 0
Ipeak = ±12.5 mA
SA SB continuous
5 mA
Current through AD or BD
± 150 mA
P1, P2, P3, LD to GND
–0.4 to VCC + 0.4 V
ESD Immunity (Human Body Model)
1500 V min
Maximum power dissipation,1TA = 70°C
TA = 85°C
1.67 W
1.33 W
Notes:
1. Thermal limiting circuitry on chip will shut down the circuit at a junction temperature of about 165°C. The
device should never see this temperature. Operation above 145°C junction temperature may degrade
device reliability.
2. Rise time of VBH (dv/dt) must be limited to less than 27 v/µs.
Operating Ranges
Operating ranges define those limits between which device functionality is guaranteed. Functionality
of the device from 0°C to 70°C is guaranteed by production testing. Performance from –40°C to
85°C is guaranteed by characterization and periodic sampling of production units.
Environmental Ranges
Ambient Temperature
0 to 70°C Commercial
–40 to +85 °C extended temperature
Ambient Relative Humidity
15 to 85%
Electrical Maximum Ranges
VCC
VBL
VBH
BGND with respect to GND
Load resistance on VTX to Vref
Load resistance on VSAB to Vref
Note:
Vloopmax:
Vpk:
5 V ± 5%
–(Vloopmax + 6 V + Vpk) to VBH V
–42.5 V to –99 V
–100 mV to +100 mV
20 kΩ minimum
20 kΩ minimum
Maximum expected loop voltage in application; ILOOP • off-hook loop resistance.
Peak signal voltage for application.
Am79R241 Datasheet
15
SPECIFICATIONS
Target Specifications (See note 1)
No.
1
Item
Condition
Two-wire loop voltage
(including offset)
Standby mode, open circuit,
|VBH| < 55 V
|VBH| > 55 V
Any Active mode (does not
include OHT), RL = 600 Ω,
IRSN = 50 µA
OHT mode, RL = 2200 Ω,
IRSN = 20 µA
2
Feed resistance per leg at
pins AD & BD
Standby mode
3
Feed current limit
Feed current
Standby mode, RL = 600 Ω
IMT current
Standby mode, RL = 2200 Ω
ILG current
Standby mode
A to VBH
B to Ground
4
5
Ternary input voltage
boundaries for LD pin.
Mid-level input source
must be Vref.
Low boundary
Mid boundary
High boundary
Input high current
Input low current
Mid-level current
Logic Inputs P1, P2, P3
Input high voltage
Input low voltage
Input high current
Input low current
6
VTX output offset
7
VREF input current
VREF = 1.4 V
8
CREF input current
CREF = 3.3 V
9
β, DC Ratio of VSAB to
loop voltage:
Tj < 145°C, VSA – VSB = 22 V
V SAB
β = ------------------------V SA – V SB
10
Fault Indicator Threshold
11
Gain from VLB pin to A or
B pin, KLG
12
VLB pin input current
Voltage Output on IMT
Min
VBH – 8
48
13.88
Typ
VBH–7
51
15
Max
Unit
Note
V
3
3
VBH–6
55.5
16.13
19.8
22
130
250
375
Ω
34
45
mA
44.6
56
µA
36
43
0.6
VREF+0.3
VREF–0.3
CREF – 1
108
47
51
2.0
-20
-20
0
0
0.8
20
20
–50
0
+50
50
V
V
V
µA
µA
µA
V
V
µA
µA
mV
µA
3
-3
0
3
µA
3
0.0088
0.0097
0.0106
V/V
TBD
CREF –
0.3 V
CREF
V
30
VLB = VREF ± 1 V
0
100
µA
ILOOP/IMT
ILOOP = 10 mA
275
300
325
A/A
14
ILONG/ILG
ILONG = 10 mA
565
605
645
A/A
15
Input current, SA and SB
pins
Active modes
1.0
3.0
µA
16
K1
Incremental DC current gain
462.5
500
537.5
17
ISA/IMT
Disconnect ISA = 2 mA
4
6
8.75
18
ISB/ILG
Disconnect ISB = 2 mA
19
VSAB output offset
20
IMT output offset
–3
21
ILG output offset
–1
3
3
3
A/A
10
12
16
TBD
TBD
TBD
mV
0
3
µA
0
1
µA
Am79R241 Datasheet
3
V/V
13
16
—
—
—
3
3
3
Relay Driver Specifications
Item
On Voltage
Condition
Min
25 mA/relay sink
Typ
Max
0.4
0.5
Unit
Note
V
Figure 5.
40 mA/relay sink
0.8
1.0
R2,R3 Off Leakage
R2,R3 = BGND
RYE = VBH
0
100
Zener Break Over
Iz = 100 µA
6.6
7.9
10
V
Zener On Voltage
Iz = 30 mA
6
11
17
V
µA
Relay Driver Configuration
R2
R3
RYE
BGND
BGND
Figure 5A. Relay 1 Driver
R1
BGND
Am79R241 Datasheet
17
Am79R241 Transmission Specifications
No.
Item
Condition
Min
1
RSN input impedance
2
VTX output impedance
f = 300 to 3400 Hz
3
Max, AC + DC loop current
Active High Battery or Active
Low Battery
4
Longitudinal impedance,
A or B to GND
Active mode
5
2-4 wire gain
–10 dBm, 1 kHz, 0 to 70°C
TA = –40°C to 85°C
–14.13
–14.18
6
2-4 wire gain variation with
frequency
300 to 3400 Hz, relative to 1 kHz
TA = –40°C to 85°C
7
2-4 wire gain tracking
+3 dBm to –55 dBm
Reference: –10 dBm
TA = –40 to 85°C
Max
1
Unit
Ω
3
70
Note
3
mA
Ω
70
135
–13.98
–13.98
–13.83
–13.78
—
3
–0.1
–0.15
+0.1
+0.15
—
3
–0.1
+0.1
3,6
–0.15
+0.15
dB
8
4-2 wire gain
–10 dBm, 1 kHz
TA = –40°C to 85°C
–0.15
–0.2
+0.15
+0.2
—
3
9
4-2 wire gain variation with
frequency
300 to 3400 Hz, relative to 1 kHz
–0.1
+0.1
—
1
10
4-2 wire gain tracking
+3 dBm to –55 dBm
Reference: –10 dBm
–40°C to 85°C
–0.1
–0.15
+0.1
+0.15
3, 6
11
Total harmonic distortion level
2-wire
4-wire overload level at VTX
300 Hz to 3400 Hz
0 dBm
11.2 dBm
–12 dBm
–0.8 dBm
RLOAD = 600 Ω
OHT
VAB - 50 V 0 dBm
Idle channel noise
C-message
Active modes, RL = 600 Ω
2-wire
TA = –40 to 85°C
4-wire
2-wire
TA = –40 to 85°C
4-wire
4-wire
11B
12
Psophometric
Weighted
13
Longitudinal balance
(IEEE method)
Normal Polarity
+7
TBD
–7
–83
TBD
–97
L-T
200 to 1000 Hz
TA = –40°C to 85°C
1000 to 3400 Hz
TA = –40°C to 85°C
58
53
53
48
T-L
40
200 to 3400 Hz
–50
–40
–48
–38
dB
dB
dB
dB
Vp
—
—
—
—
3
+11
dBrnC
–79
dBmp
—
3
—
—
3
—
±1
L - T, IL = 0 50 to 3400 Hz
18
Typ
—
3
—
3
63
4
Reverse Polarity
L-T
200 to 1000 Hz
TA = –40°C to 85°C
50
48
14
PSRR (VBH, VBL)
50 to 3400 Hz
3.4 to 50 kHz
25
45
40
4, 5
2, 3, 5
15
PSRR (VCC)
50 to 3400 Hz
3.4 to 50 kHz
25
45
35
4, 5
2, 3, 5
16
Longitudinal AC current per wire
F = 15 to 60 Hz Active mode
20
30
17
Metering distortion
Freq = 12 kHz 2.8 Vrms
Freq = 16 kHz
metering load = 200 Ω
40
Am79R241 Datasheet
dB
—
3
mArms
3
dB
3
Am79R241 Ringing Specifications
Item
Peak Ringing Voltage
Condition
Min
Typ
Active Internal Ringing
VBH+3
Max
Unit
Note
GND–3
V
8
Am79R241 Current-Limit Behavior
SLIC Mode
Disconnect
Condition
Min
Applied fault between ground and T/R
VBH applied to Tip or Ring
Typ
Max
Unit
Note
1
VBH/200K
100
µA
A
7
Tip Open
Ring Short to GND
24
35
46
Standby
Short Tip-to-VBH
Short Ring-to-GND
24
26
38
35
47
44
Active Ringing
ISLAC generating internal ringing
mA
100
3
Am79R241 Fault Indications
Fault
Indication
Unit
No Fault
IMT operates normally (Vref ±1V)
Thermal Shutdown
IMT above 2.8 V
Note
Notes:
1. Unless otherwise specified, test conditions are: VCC = 5 V, RMG1 = RMG2 = 1 kΩ, BATH = –90 V,
BATL = –36 V, RRX = 150 kΩ, RL = 600 Ω, RSA = RSB = 200 kΩ, RFA = RFB = 50 Ω, CHP = 22 nF,
CAD = CBD = 22 nF, IRSN = 50 µA, Active low battery. DC-feed conditions are normally set by the
ISLAC device. When the Am79R241 is tested by itself, its operating conditions must be simulated as
if it were connected to an ideal ISLAC device.
30 K
30 K
RT Network
390 pf
VREF
2. These tests are performed with the following load impedances:
Frequency < 12 kHz – Longitudinal impedance = 500 Ω; metallic impedance = 300 Ω
Frequency > 12 kHz – Longitudinal impedance = 90 Ω; metallic impedance = 135 Ω
3. Not tested or partially tested in production. This parameter is guaranteed by characterization or correlation
to other tests.
4. This parameter is tested at 1 kHz in production. Performance at other frequencies is guaranteed by
characterization.
5. When the Am79R241 and ISLAC device is in the anti-sat operating region, this parameter is degraded. The
exact degradation depends on system design.
6. –55 dBm gain tracking level not tested in production. This parameter is guaranteed by characterization and
correlation to other tests.
7. This spec is valid from 0 V to VBL or –50 V, whichever is lower in magnitude.
8. Other ringing-voltage characteristics are set by the ISLAC device.
Am79R241 Datasheet
19
Operating Modes
The Am79R241 receives multiplexed control data on the P1, P2 and P3 pins. The LD pin then
controls the loading of P1, P2, and P3 values into the proper bits in the Am79R241 control register.
When the LD pin is less than 0.3 V below VREF ( < (VREF – 0.3 V) ), P1–P3 must contain data for
relay control bits RD1, RD2 and RD3. These are latched into the first three bits in the Am79R241
control register. When the LD pin is more than 0.3 V above VREF (> (VREF + 0.3 V) ), P1–P3 must
contain ISLIC control data C1, C2, and C3, which are latched into the last three bits of the Am79R241
control register. Connecting the LD pin to VREF locks the contents of the Am79R241 control register.
The operating mode of the Am79R241 is determined by the C1, C2, and C3 bits in the control register
of the Am79R241. Table 1 defines the Am79R241 operating modes set by these signals.
Under normal operating conditions, the ISLIC device does not have active relays. The Am79R241
to ISLAC device interface is designed to allow continuous real-time control of the relay drivers to
avoid incorrect data loads to the relay bit latches of the Am79R241 devices.
To perform external ringing, the ISLAC device from the Intelligent Access voice family is set to
external ringing mode (RMODE = 1), enables the ring relay, and puts the Am79R241 in the Standby
mode.
Table 1.
Operating Modes
Connection to
RMGPi & RMGLi
Resistors
Battery Voltage
Selection
Operating Mode
Standby1
High Battery
(BATH) and BGND
(High ohmic feed): Loop supervision
active, A and B amplifiers shut down
Open
1
Tip Open1
High Battery
(BATH) and BGND
Tip Open: AD at High-Impedance,
Channel A power amplifier shut
down
Open
1
0
On-Hook
Transmission, Fixed
Longitudinal Voltage
High Battery
(BATH) and BGND
Fixed longitudinal voltage of –28 V
0
1
1
Disconnect
Low Battery
selection at VBL
AD and BD at High-Impedance,
Channel A and B power amplifiers
shut down
1
0
0
RSVD
1
0
1
Active High Battery
High Battery
(BATH) and BGND
1
1
0
Active Low Battery
Low Battery (BATL)
and BGND
1
1
1
Active Internal Ringing
High Battery
(BATH) and BGND
C3
C2
C1
0
0
0
0
0
0
Operating Mode
A and B Amplifier
Output
Active feed, normal or reverse
polarity
Active internal ringing
Note:
1.
In these modes, the ring lead (B-lead) output has a –50 V internal clamp to battery ground (BGND).
20
Am79R241 Datasheet
Table 2.
Mode Descriptions
Operating
Mode
Disconnect
Description
This mode disconnects both A and B output amplifiers from the AD and BD outputs. The
A and B amplifiers are shut down and the Am79R241 selects the low battery voltage at the
VBL pin. In the Disconnect state, the currents on IMT and ILG represent the voltages on
the SA and SB pins, respectively. These currents are scaled to produce voltages across
V
400
V
400
SA
SB
RMTi and RLGi of ---------- and ---------- , respectively.
Standby
The power amplifiers are turned off. The AD output is driven by an internal 250 Ω (typical)
resistor, which connects to ground. The BD output is driven by an internal 250 Ω (typical)
resistor, which connects to the high battery (BATH) at the VBH pin, through a clamp circuit,
which clamps at –50 V with respect to BGND. For VBH values above –55 V, the open-circuit
voltage, which appears at this output is ~VBH + 5 V. If VBH is below –55 V, the voltage at
this output is –50 V. The battery selection for the balance of the circuitry on the chip is VBL.
Line supervision remains active. Current limiting is provided on each line to limit power
dissipation under short-loop conditions as specified in the “Am79241 Current-Limit
Behavior” section. In external ringing, the standby ISLIC state is selected.
Tip Open
In this mode, the AD (Tip) lead is opened and the BD (Ring) lead is connected to a clamp,
which operates from the high battery on VBH pin and clamps to approximately –50 V with
respect to BGND through a resistor of approximately 250 Ω (typical). The battery selection
for the balance of the circuitry on the chip is VBL. To prevent excessive power dissipation,
the current in the Ring lead is limited by an internal current source to 30 mA.
Active High
Battery
In the Active High Battery mode, battery connections are connected as shown in Table 1.
Both output amplifiers deliver the full power level determined by the programmed DC-feed
conditions. Active High Battery mode is enabled during a call in applications when a long
loop can be encountered.
Active Low
Battery
Both output amplifiers deliver the full power level determined by the programmed DC-feed
conditions. VBL, the low negative battery, is selected in the Active Low Battery mode. This
is typically used during the voice part of a call.
Active
Internal
Ringing
In the Internal Ringing mode, the Am79R241 selects the battery connections as shown in
Table 1. When using internal ringing, both the AD and BD output amplifiers deliver the
ringing signal determined by the programmed ringing level.
On-Hook
Transmission
(OHT), Fixed
Longitudinal
Voltage
In the On-Hook Transmission, Fixed Longitudinal Voltage mode, battery connections are
connected as shown in Table 1. The longitudinal voltage is fixed at –30 V to allow compliance
with safety specifications for some classes of products.
Control bits RD1, RD2, and RD3 do not affect the operating mode of the Am79R241. These signals
usually perform the following functions.
Am79R241 Datasheet
21
Table 3.
Driver Descriptions
Driver
Description
R1
A logic 1 on RD1 turns the R1 driver on and operates a relay connected between the R1
pin and VCCD. R1 drives the ring relay when external ringing is selected.
R2
A logic 1 on the RD2 signal turns the R2 driver on and routes current from the R2 pin to
the RYE pin. In the option where the RYE pin is connected to ground, the R2 pin can sink
current from a relay connected to VCCD.
Another option is to connect the RYE pin to the BD (Ring) lead and connect a test load
between R2 and the AD (Tip) lead. This technique avoids the use of a relay to connect a
test load. However, it does not isolate the subscriber line from the linecard. The test load
must be connected to the Am79R241 side of the protection resistor to avoid damage to
the R2 driver.
R3
A logic 1 on the RD3 signal turns the R3 driver on and routes current from the R3 pin to
the RYE pin. In the option where the RYE pin is connected to ground, the R3 pin can sink
current from a relay connected to VCCD.
Another option is to connect the RYE pin to the B (Ring) lead and connect a test load
between R3 and the A (Tip) lead. This technique avoids the use of a relay to connect a
test load. However, it does not isolate the subscriber line from the linecard. The test load
must be connected to the Am79R241 side of the protection resistor to avoid damage to
the R3 driver.
Thermal-Management Equations (All Modes except Standby)
IL < 5 mA
TMG resistor-current is limited to be 5 mA < IL.
If IL < 5 mA, no current flows in the TMG resistor
and it all flows in the Am79R241.
PSLIC = (SBAT – ILRL) • IL + 0.3 W
PTMG = 0
IL > 5 mA
PSLIC = (SBAT – IL(R L + 2 • R FUSE))*IL + 0.3 W – PTMG
PTMG = (IL – 5 mA)^2 • (RTMG1 + RTMG2)
These equations are valid when
RTMGX • (IL – 5 mA) < (SBAT – RLIL)/2 – 2
because the longitudinal voltage is one-half the
battery voltage and the TMG switches require
approximately 2 V.
TIMING SPECIFICATIONS
Symbol
Signal
Parameter
Min
trSLD
LD
Rise time Am79R241 LD pin
tfSLD
LD
Fall time Am79R241 LD pin
tSLDPW
LD
LD minimum pulse width
tSDXSU
P1,P2,P3
P1–3 data Setup time
4.5
tSDXHD
P1,P2,P3
P1–3 data hold time
4.5
tSDXD
P1,P2,P3
Max P1–3 data delay
Typ
Max
Unit
2
2
3
µs
5
Notes:
1. The P1–3 pins are updated continuously during operation by the LD signal.
2. After a power-on reset or hardware reset, the relay outputs from the Am79R241 turn all relays off. An
unassuming state is to place the relay control pins, which are level triggered, to a reset state for all relays.
Any noise encountered only raises the levels toward the register lock state.
3. When writing to the ISLIC registers, the sequence is:
a. Set LD pin to mid-state
b. Place appropriate data on the P1–3 pins
c. Assert the LD pin to High or Low to write the proper data
d. Return LD pin to mid-state
4. Am79R241 registers are refreshed at 5.33 kHz when used with an ISLAC device.
5. If the clock or MPI becomes disabled, the LD pins and P1–3 returns to 0 V state, thus protecting the
Am79R241 and the line connection.
6. Not tested in production. Guaranteed by characterization.
22
Am79R241 Datasheet
WAVEFORMS
Write State Register
VCC
LD
VREF
Lock Registers
0V
Write Relay Register
Previous
P1,P2,P3 Relay Data
Relay Data
State Data
New Relay
Data
DETAIL A
VREF
LD
Write State Register
tr SLD
tf SLD
VREF
Write Relay Register
t SLDPW
t SDXSU
t SDXHD
P1,P2,P3
Am79R241 Datasheet
23
PHYSICAL DIMENSIONS
.447
.453
.485
.495
.009
.015
.585
.595
.042
.056
.125
.140
Pin 1 I.D.
.080
.095
.547
.553
SEATING
PLANE
.400
REF.
.490
.530
.013
.021
.050 REF.
.026
.032
TOP VIEW
SIDE VIEW
16-038FPO-5
PL 032
DA79
6-28-94 ae
REVISION SUMMARY
Revision H to Revision I
•
Page 11, Figure 3, DT1i was added and the last note was modified.
•
Page 12, Figure 4, DT1i was added and the last note was modified.
•
Page 15, Electrical Characteristics, Numbers changed in the Max column.
•
Page 16, Absolute Maximum Ratings, The "Humidity" row was deleted.
•
Page 17, Specifications, There were changes to rows one, four, six, 12, and 17–21, and to the Note column.
•
Page 18, Relay Driver Specifications, There were changes in the last two rows.
•
Page 19, Transmission Specifications, There were changes to rows, six, eight, 10, and 13, and to the Note column.
•
Page 20, Fault Indications, "ILG operates normally" was deleted from the Indication column on the second row.
24
Am79R241 Datasheet
Notes:
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