Intelligent Access™ Voice Solutions Am79R251 Intelligent Subscriber Line Interface Circuit (ISLIC™) DISTINCTIVE CHARACTERISTICS ■ Monitor of two-wire interface voltages and currents supports ■ Supports internal and external ringing — High voltage operation supports long loops — Voice transmission ■ +5 V and battery supplies — Through chip ring generation ■ Dual battery operation for system power saving — Programmable DC feed characteristics — Automatic battery switching — Independent of battery — Intelligent thermal management — Current limited ■ Compatible with inexpensive protection networks — Selectable off-hook and ground-key thresholds — Subscriber line diagnostics — Accommodates low tolerance fuse resistors or PTC thermistors — Leakage resistance ■ Metering capable — Loop resistance — Line capacitance — 12 kHz and 16 kHz — Bell capacitance — Smooth polarity reversal ■ Tip-open state supports ground start signaling — Foreign voltage sensing — Power cross and fault detection ■ Integrated test load switches/relay drivers BLOCK DIAGRAM RSN Signal Transmission AD VTX SA HPA HPB Two-Wire Interface Longitudinal Control Gain/Level Shift VLB SB BD Attenuator VSAB VREF TMN TMP Signal Conditioning Thermal Management Control IMT ILG TMS Fault Meas VBP CREF VBL Switch Driver VBH Relay Control R2 R3 RYE Relay Drivers P1 Input Decoder and Control Registers P2 P3 LD R1 Relay Driver 1 BGND GND VCC Pub. # 22480 Rev: C Amendment: /0 Issue Date: December 1999 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 Am79R251 . . . . . . . . . . . . . . . . . . . . . . . . . 11 Linecard Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Operating Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Environmental Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Electrical Maximum Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Target Specifications (See note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Relay Driver Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Am79R251 Transmission Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Am79R251 Ringing Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Am79R251 Current-Limit Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Am79R251 Fault Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Thermal-Management Equations (All Modes except Standby) . . . . . . . . . . . . . . . . . . 23 Timing Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Physical Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 PL032 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Revision Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Revision A to Revision B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Revision B to Revision C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2 Am79R251 The Am79R251, 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 Am79R251 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 ■ Exceeds LSSGR and CCITT central office requirements ■ Two chip solution supports high density, multichannel architecture ■ Selectable PCM or GCI interface ■ Single hardware design meets multiple country requirements through software programming of: — Ringing waveform and frequency — Supports most available master clock frequencies from 512 kHz to 8.192 MHz ■ On-hook transmission ■ Power/service denial mode — DC loop-feed characteristics and current-limit ■ Line-feed characteristics independent of battery voltage — Loop-supervision detection thresholds ■ Only 5 V, 3.3 V and battery supplies needed — Off-hook debounce circuit ■ Low idle-power per line — Ground-key and ring-trip filters ■ Linear power-feed with intelligent powermanagement feature — Off-hook detect de-bounce interval — Two-wire AC impedance ■ Compatible with inexpensive protection networks; Accommodates low-tolerance fuse resistors while maintaining longitudinal balance — Transhybrid balance — Transmit and receive gains — Digital I/O pins ■ Monitors two-wire interface voltages and currents for subscriber line diagnostics — A-law/µ-law and linear selection ■ Built-in voice-path test modes — Equalization ■ Supports internal and external battery-backed ringing — Self-contained ringing generation and control ■ Power-cross, fault, and foreign voltage detection ■ Integrated line-test features — Supports external ringing generator and ring relay — Leakage — Line and ringer capacitance — 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 ■ Adaptive transhybrid balance — Continuous or adapt and freeze ■ 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 ■ Supports both loop-start and ground-start signaling Am79R251 3 BLOCK DIAGRAMS Figure 1. 4 Example Four-Channel Linecard Block Diagram Am79R251 Figure 2. Am79R251 Block Diagram AD IA sense IA RSN IA 600 SA + A Amplifier - Fault Meas. + HPA Active High Voltage + VBP Power Amplifiers Positive Supply TMS VTX VREF BGND + HPB Fault Meas. + + β = 0.00667 - SB B Amplifier IB VSAB VREF IB sense BD VREF IB 600 TMN TMP VREF Thermal Management Control Gain/Level Shift To Power Amplifiers Thermal Shutdown VBH IA IB + 600 600 IMT IA IB − 600 600 ILG Disconnect Active Low Battery Internal Ringing Standby Active Boosted Battery Active High Battery RYE OHT Fixed Longitudinal Voltage VBL Tip Open High Neg Batt Sel R3 VLB Decoder R2 CREF RD1 RD2 R1 BGND RD3 C1 C2 Control Register C3 Demux P1 P2 P3 Am79R251 LD VCC GND 5 ORDERING INFORMATION AMD 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. Am79R251 J C TEMPERATURE RANGE C= Commercial (0°C to +70°C)* PACKAGE TYPE J = 32-pin plastic leaded chip carrier (PL032) DEVICE NAME/DESCRIPTION Am79R251 Intelligent Subscriber Line Interface Circuit Valid Combinations Valid Combinations Am79R251 Valid combinations list configurations planned to be supported in volume for this device. Consult the local AMD sales office to confirm availability of specific valid combinations, and to check on newly released valid combinations. JC 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 Am79R251 AD 1 32 31 30 VBP 2 BD VCC 4 3 BGND VBH VBL CONNECTION DIAGRAM R1 5 29 SB R2 6 28 SA RYE 7 27 IMT R3 8 26 ILG 25 CREF Am79R251 32-Pin PLCC TMS 9 TMP 10 24 RSVD TMN 11 23 HPB P1 12 22 HPA P2 13 21 VTX Am79R251 VREF RSN VLB GND VSAB LD P3 14 15 16 17 18 19 20 7 PIN DESCRIPTIONS Pin 8 Pin Name I/O O Description AD, BD A, B Line Drivers BGND Ground Provide the currents to the A and B leads of the subscriber loop. 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 Analog and digital ground return for VCC. 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. 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 Am79R251 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 Am79R251 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 Am79R251 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 AMD 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 Am79R251. 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. VBP Positive Battery (Power) Used in Ringing State and for Extended Loop operation. VCC +5 V Power Supply VLB Longitudinal Voltage I Sets the DC longitudinal voltage of the Am79R251. It is the reference for the longitudinal control loop. When the VLB pin is greater than VREF, the Am79R251 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. VREF 1.4 V Analog Reference I The ISLAC chip provides this voltage which is used by the Am79R251 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. Positive supply for low voltage analog and digital circuits in the Am79R251. Am79R251 GENERAL DESCRIPTION The Intelligent Access voice chipsets integrate all functions of the subscriber line. Two chip types are used to implement the linecard; an Am79R251 device and an ISLAC device. These provide the following basic functions: 1. The Am79R251: 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 Am79R251. Complete schematics of linecards using the Intelligent Access voice chipsets for internal and external ringing are shown in Figure 3 and Figure 4. The Am79R251 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 Am79R251 is designed to be used exclusively with the ISLAC devices. The Am79R251 requires only +5 V power and the battery supplies for its operation. The Am79R251 implements a linear loop-current feeding method with the enhancement of intelligent Thermal Management. This limits the amount of power dissipated on the Am79R251 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 WinSLAC 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 Am79R251 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 Am79R251 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 Am79R251 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 Am79R251 INTELLIGENT ACCESS™ VOICE CHIPSETS LINECARD WITH Am79R251 Figure 3. Internal Ringing Linecard Schematic +5V VCC RSAi 3.3V CREF SA RRXi VOUTi RSN DGND RHLai A RFAi RHLbi CHLbi AD VHLi RTESTMi U3 RHLci U5 RTi RHLdi CHLdi AGND VREF CADi VCCA VSABi VSAB CHPi BATH CS1 CS2 U4 U6 VCC +3.3VDC VCCD HPA BATP DT1i VTX VINi VLB VLBi IMT VIMTi HPB CSSi B RFBi BD RSBi SB CBDi TMS DT2i RMTi U1 Am79R251 U2 ISLAC VREF RMGPi VILGi ILG BACK PLANE TMP RLGi TMN VREF RMGLi DHi BATH VREF VBH VREF DLi BATL VBL LD LDi SBP GND CBATHi CBATLi P1 CBATPi P1 SLB BATL RSLB P2 P2 P3 P3 SHB BATH RSHB VBP BATP BATP RSPB RYE IREF R2 RREF RTESTLi R3 R1 BGND RSVD * CSS required for > 2.2 VRMS metering ** Connections shown for one channel Am79R251 11 Figure 4. External Ringing Linecard Schematic RSAi +5 V 3.3 V VCC SA CREF RRXi VOUTi RSN RHLai RFAi A RHLbi CHLbi AD DGND KRi(A) VHLi U3 RHLci CADi U5 RTi RTESTMi CHPi BATH CS1 HPA VSABi VCCD HPB U6 CSSi RFBi VLB VLBi IMT VIMTi CBDi BD KRi (B) VCC +3.3 VDC VINi VTX CS2 BATP U4 B VREF VCCA VSAB DT1i AGND RHLdi CHLdi RSBi RMTi SB TMS DT2i U1 Am79R251 VREF VILGi ILG U2 ISLAC RMGPi RLGi BACK PLANE TMP VREF TMN VREF VREF RMGLi DHi BATH VBH LD LDi GND DLi BATL VBL CBATHi CBATLi P1 P1 P2 P2 P3 P3 BATP SPB RSPB SLB BATL RSLB CBATPi SHB VBP BATP BATH RSHB RYE IREF R2H RREF RTESTLi R3H R1 RGFDLi KRi BGND RSVD +5V * CSS required for > 2.2 VRMS metering ** Connections shown for one channel Ring Bus RSRBi RSRC 12 Am79R251 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 Am79R251 U2 Am79X22xx U3, U4 P1001SC U5, U6 Value Tol. Rating Comments ISLIC device ISLAC device 100 V — — TECCOR Battrax protector TECCOR D1, D2 Diode 1A 100 V DHi, DLi, DT1i, DT2i Diode 100 mA 100 V RFAi, RFBi Resistor 50 Ω 2% 2W Fusible PTC protection resistors RSAi, RSBi Resistor 200 kΩ 2% 1/4 W Sense resistors RTi Resistor 80.6 kΩ 1% 1/8 W RRXi Resistor 100 kΩ 1% 1/8 W RREF Resistor 69.8 kΩ 1% 1/8 W Current reference RMGLi, RMGPi Resistor 1 kΩ 5% 1W Thermal management resistors RSHB, RSLB Resistor 750 kΩ 1% 1/8 W RHLai Resistor 40.2 kΩ 1% 1/10 W 50 ns RHLbi Resistor 4.32 kΩ 1% 1/10 W RHLci Resistor 2.87 kΩ 1% 1/10 W RHLdi Resistor 2.87 kΩ CHLbi Capacitor 3.3 nF 10 % 10 V Not Polarized Ceramic 1% 1/10 W 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 RTESTMi Resistor 2 kΩ 1% 1W Metallic test Resistor 2 kΩ 1% 1W Longitudinal test Capacitor 22 nF 10% 100 V Ceramic, not voltage sensitive Capacitor 100 nF 20% 100 V Ceramic RTESTLi CADi, CBDi 1 CBATHi, CBATLi, CBATPi CHPi CS1i, CS2i1 CSSi3 Capacitor 22 nF 20% 100 V Ceramic Capacitor 100 nF 20% 100 V Protector speed up capacitor Capacitor 56 pF 5% 100 V Ceramic Components for External Ringing RGFDi Resistor 510 Ω 2% 2W 1.2 W typ RSRBi, RSRc Resistor 750 kΩ 2% 1/4 W Matched to within 0.2% for initial tolerance and 0 to 70° C ambient temperature range.2 17 mW typ KRi Relay 5 V Coil 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. Am79R251 13 ELECTRICAL CHARACTERISTICS Power Dissipation Loop resistance = 0 to ∞ unless otherwise noted (not including fuse resistors), 2 x 50 Ω fuse resistors, BATL = -40 V, BATH = –68 V, BATP = +52 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 • RTMG1 = RTMG2 (Thermal management resistors) = 1 kΩ Description Power Dissipation Normal Polarity Test Conditions TBD On-Hook Standby TBD On-Hook Transmission Fixed Longitudinal Voltage ISLIC TBD On-Hook Active High Battery ISLIC TBD Off-Hook Active Low Battery RL = 294 Ω TBD ISLIC TMG TBD VBH VBL VCC TBD On-Hook Transmission Fixed Longitudinal Voltage VBH VBL VCC TBD On-Hook Active High Battery VBH VBL VCC TBD VBH VBL VCC TBD Off-Hook Active Low Battery RL = 294 Ω Am79R251 Max Unit mW VBH VBL VCC On-Hook Standby 14 Typ On-Hook Disconnect On-Hook Disconnect Power Supply Currents Min mA Thermal Resistance The junction to air thermal resistance of the Am79R251 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 Humidity TBD VCC with respect to GND –0.4 to +7 V VBH, VBL with respect to GND +0.4 to –85 V VBP with respect to GND –0.4 to +85 V VBP with respect to VBH 150 V BGND with respect to GND –3 to +3V Voltage on R1 relay outputs +7 V 2 AD or BD to BGND: Continuous VBH – 1 to VBP + 1 10 ms (F = 0.1 Hz) VBH – 5 to VBP + 5 1 µs (F = 0.1 Hz) VBH – 10 to VBP + 10 250 ns (F = 0.1 Hz) VBH – 15 to VBP + 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 Note 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. Note 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% Am79R251 15 Electrical Maximum Ranges VCC 5 V ± 5% VBL –(Vloopmax + 6V + Vpk) to VBH V VBH –18 V to –79 V VBP +79 V to +8 V Maximum supply voltage across device, VBP–VBH 140 V BGND with respect to GND –100 mV to +100 mV Load resistance on VTX to Vref 20 kΩ minimum Load resistance on VSAB to Vref 20 kΩ minimum Note: Vloopmax: Vpk: 16 Maximum expected loop voltage in application; ILOOP • off-hook loop resistance. Peak signal voltage for application. Am79R251 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 = 600 Ω, IRSN = 36 µA 2 Feed resistance per leg at pins AD & BD Standby mode 3 Feed current limit Feed current Standby mode, RL = 600 Ω 4 5 IMT current Standby mode, RL = 1930 Ω ILG current Standby mode A to VBH B to Ground Ternary input voltage boundaries for LD pin. Mid-level input source must be Vref. Low 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 Min Typ Max VBH – ? VBH–? 13.88 VBH–5 50 15 8.64 10.8 12.96 130 250 375 Note V 3 16.13 30 44.6 Unit Ω mA 56 µA 36 43 0.6 CREF – 1 TBD TBD TBD 2.0 0.8 10 50 –50 +50 V V µA µA V — — — — 3 V V µA µA 6 VTX output offset 7 VREF input current VREF = 1.4 V TBD mA mV 3 8 CREF input current CREF = 3.3 V TBD mA 3 9 β, DC Ratio of VAB to loop Tj < 145°C, VSA – VSB = 22 V 0.00667 V/V V SAB voltage: β = ------------------------- V SA – V SB 10 Fault Indicator Threshold 11 Gain from VLB pin to A or B pin 12 VLB pin input current 13 14 Voltage Output on IMT TBD CREF 0.3 V CREF V 45 V/V VLB = VREF ±1V TBD mA ILOOP/IMT ILOOP = 10 mA 300 A/A ILONG/ILG ILONG = 10 mA 600 A/A 15 Input current, SA and SB pins Active modes 1.0 16 K1 Incremental DC current gain 500 17 ISA/IMT Disconnect, ISA = 2 mA 6 18 ISB/ILG Disconnect, ISB = 2 mA 12 Am79R251 3.0 µA 3 3 A/A 17 Relay Driver Specifications Item On Voltage R2,R3 Off Leakage Figure 5. Condition Min 25 mA/relay sink 1 relay on 3 relays on 40 mA/ relay sink 1 relay on 3 relays on R2,R3 = BGND RYE = VBH Zener Break Over, R1 Iz = 100 µA Zener On Voltage, R1 Iz = 30 mA Typ Max 0.225 0.4 0.3 0.5 0.45 0.8 0.7 1.0 0 6.6 100 V Note 3 3 µA 7.9 V 11 V Relay Driver Configuration R3 R2 RYE Figure 5A. Ring Relay R1 BGND 18 Unit Am79R251 Am79R251 Transmission Specifications No. Item Condition Min f = 300 to 3400 Hz Typ Max 1 RSN input impedance 1 2 VTX output impedance 3 Max, AC + DC loop current Active High Battery or Active Low Battery 4 Input 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 6 2-4 wire gain variation with frequency 300 to 3400 Hz, relative to 1 kHz TA=–40°C to 85°C –0.1 +.1 7 2-4 wire gain tracking +3 dBm to –55 dBm Reference: –10 dBm TA = –40 to 85°C –0.1 +0.1 3 70 –14.13 –14.18 70 135 –13.98 –13.98 –13.83 –13.78 8 4-2 wire gain –10 dBm, 1 kHz TA= –40°C to 85°C –0.15 9 4-2 wire gain variation with frequency 300 to 3400 Hz, relative to 1 kHz –0.1 +0.1 10 4-2 wire gain tracking +3 dBm to –55 dBm Reference: –10 dBm –0.1 +0.1 11 Total harmonic distortion level 2-wire 300 Hz to 3400 Hz 0 dBm 11.2 dBm –12 dBm -0.8 dBm RLOAD = 600 Ω 4-wire 4-wire overload level at VTX 12 Idle channel noise C-message Weighted Psophometric Weighted 13 Longitudinal balance (IEEE method) Normal Polarity Note Ω 3 mA 3 Ω 6 dB TBD 0 TBD Unit +0.15 6 dB dB dB dB Vp 3 +11 dBrnC 3 –79 dBmp –50 –40 –48 –38 ±1 Active modes, RL = 600 Ω +7 TBD –7 –83 TBD –97 2-wire TA = –40 to 85°C 4-wire 2-wire TA = –40 to 85°C 4-wire L-T 200 to 1000 Hz TA = –40°C to 0°C/70°C to 85°C 1000 to 3400 Hz TA = –40°C to 0°C/70°C to 85°C 58 53 53 48 T-L 40 200 to 3400 Hz L - T, IL = 0 50 to 3400 Hz 3 63 58 63 4 Reverse Polarity L-T 200 to 1000 Hz TA = –40°C to 0°C/70°C to 85°C 50 48 14 PSRR (VBH, VBL, VBP) 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 mArms 3 17 Metering distortion Freq = 12 kHz 2.8 Vrms Freq = 16 kHz metering load = 200 Ω 40 dB 3 Am79R251 dB 19 Am79R251 Ringing Specifications Item Peak Ringing Voltage Condition Min Active Internal Ringing VBH+5 Typ Max Unit Note VBP–5 V 8 Am79R251 Current-Limit Behavior SLIC Mode Condition Min Typ Max Unit Note 1 VBH/200K 100 µA A 7 Disconnect Applied fault between ground and T/R VBH applied to Tip or Ring Tip Open Short to GND 30 Standby Short Tip-to-VBH Short Ring-to-GND 30 30 Active Ringing ISLAC generating internal ringing 100 mA Am79R251 Fault Indications Fault Indication No Fault IMT operates normally (Vref ±1V) Thermal Shutdown IMT above 2.8 V; ILG operates normally Unit Note Notes: 1. Unless otherwise specified, test conditions are: VCC = 5 V, RMG1 = RMG2 = 1 kΩ, BATH = -68 V, BATL = -40 V, BATP = +52 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. DC-feed conditions are normally set by the ISLAC device. When the Am79R251 is tested by itself, its operating conditions must be simulated as if it were connected to an ideal ISLAC device. 30 KΩ 30 KΩ 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 Am79R251 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. 20 Am79R251 Operating Modes The Am79R251 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 Am79R251 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 Am79R251 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 Am79R251 control register. Connecting the LD pin to VREF locks the contents of the Am79R251 control register. The operating mode of the Am79R251 is determined by the C1, C2, and C3 bits in the control register of the Am79R251. Table 1 defines the Am79R251 operating modes set by these signals. Under normal operating conditions, the ISLIC device does not have active relays. The Am79R251 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 Am79R251 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 Am79R251 in the Standby mode. Table 1. Operating Modes Operating Mode Battery Voltage Selection Connection to RMGPi & RMGLi Resistors C3 C2 C1 0 0 0 Standby1 High Battery (BATH) and BGND (High ohmic feed): Loop supervision active, A and B amplifiers shut down Open 0 0 1 Tip Open1 High Battery (BATH) and BGND Tip Open: AD at High-Impedance, Channel A power amplifier shut down Open 0 1 0 On-Hook Transmission, Fixed Longitudinal Voltage High Battery (BATH) and BGND Fixed longitudinal voltage of –30 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 Active Boosted Battery High Battery (BATH) and Positive Battery (BATP) 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 Positive Battery (BATP) 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). Am79R251 21 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 Am79R251 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. 22 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 opencircuit 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 “Am79R251 CurrentLimit 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 Boosted Battery In the Active Boosted Battery mode, battery connections are as shown in Table 1. Both output amplifiers deliver the full power level determined by the programmed DC-feed conditions. Active Boosted Battery mode is enabled during a call in applications when an extended loop can be encountered. Active Internal Ringing In the Internal Ringing mode, the Am79R251 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 as shown in Table 1. The longitudinal voltage is fixed at –30 V to allow compliance with safety specifications for some classes of products. Am79R251 Control bits RD1, RD2, and RD3 do not affect the operating mode of the Am79R251. These signals usually perform the following functions. 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 Am79R251 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 Am79R251 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 Am79R251. PSLIC = (SBAT – ILRL) • IL + 0.3 W PTMG = 0 IL > 5 mA PSLIC = (SBAT – IL(RL + 2 • RFUSE))*IL + 0.3 W – PTMG PTMG = (IL – 5 mA)^2 • (RTMG1 + RTMG2) Am79R251 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. 23 TIMING SPECIFICATIONS Symbol Signal Parameter Min Typ Max trSLD LD Rise time Am79R251 LD pin 2 tfSLD LD Fall time Am79R251 LD pin 2 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 3 Unit 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 Am79R251 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. Am79R251 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 Am79R251 and the line connection. 6. Not tested in production. Guaranteed by characterization. 24 Am79R251 WAVEFORMS Write State Register VCC VREF LD 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 trSLD tfSLD VREF Write Relay Register tSLDPW tSDXHD tSDXSU P1,P2,P3 Am79R251 25 PHYSICAL DIMENSIONS PL032 .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 A to Revision B • Revision A was a condensed version of the datasheet while Revision B contains the full version. Revision B to Revision C • Page 13, Linecard Parts List, Rows CHLbi and CHLdi: switched the numbers in the “Values” column. 26 Am79R251 The contents of this document are provided in connection with Advanced Micro Devices, Inc. ("AMD") products. AMD makes no representations or warranties with respect to the accuracy or completeness of the contents of this publication and reserves the right to make changes to specifications and product descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual property rights is granted by this publication. Except as set forth in AMD’s Standard Terms and Conditions of Sale, AMD assumes no liability whatsoever, and disclaims any express or implied warranty, relating to its products including, but not limited to, the implied warranty of merchantability, fitness for a particular purpose, or infringement of any intellectual property right. AMD’s products are not designed, intended, authorized or warranted for use as components in systems intended for surgical implant into the body, or in other applications intended to support or sustain life, or in any other application in which the failure of AMD’s product could create a situation where personal injury, death, or severe property or environmental damage may occur. AMD reserves the right to discontinue or make changes to its products at any time without notice. © 1999 Advanced Micro Devices, Inc. All rights reserved. Trademarks AMD, the AMD logo and combinations thereof are trademarks of Advanced Micro Devices, Inc. Intelligent Access and WinSLAC are trademarks of Advanced Micro Devices, Inc. Product names used in this publication are for identification purposes only and may be trademarks of their respective companies.