Obsolescence Notice This product is obsolete. This information is available for your convenience only. For more information on Zarlink’s obsolete products and replacement product lists, please visit http://products.zarlink.com/obsolete_products/ MH88612 Subscriber Line Interface Circuit (SLIC) Data Sheet Features November 2006 • 600 Ω line impedance • Transformerless 2-wire to 4-wire conversion • Battery and ringing feed to line • Off-hook and dial pulse detection. • Ring ground over-current protection • Adjustable constant current feed. • Relay driver • Power VBAT Denial • Wide Operating Range Ordering Information MH88612 MH886121 0°C to +70°C Description The SLIC provides a complete interface between a switching system and a subscriber loop. Functions provided include battery feed and ringing feed to the subscriber line, 2-Wire to 4-Wire hybrid interfacing, constant current feed and dial pulse detection. The device is fabricated using thick film hybrid technology in a 20-pin single in-line package. Line interface for: PABX • Intercoms • Key Telephone Systems • Control Systems Boxed Boxed *Pb Free Matte Tin Applications • 20 Pin SIL 20 Pin SIL* LPGND VBAT PD VDD VEE AGND Power Management TF TIP RING RF 2-Wire to 4-Wire Conversion Current and Voltage Sensing VR VX RV VRLY RC RD CD Over Current Protection Relay Drive Circuit Loop Supervision Constant Current Feed SHK Figure 1 - Block Diagram 1 Zarlink Semiconductor Inc. Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc. Copyright 2002-2006, Zarlink Semiconductor Inc. All Rights Reserved. VREF CAP MH88612 Data Sheet Change Summary Changes from August 2006 Issue to November 2006 Issue. Page Item Change 1 Updated Ordering Information. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 TF LPGND VR VREF VEE AGND PD VX TIP RING RF VDD RC RD RV VRLY CD VBAT CAP SHK Figure 2 - Pin Connections Pin Description Pin # Name 1 TF 2 Description Tip Feed. Connects to external diode for protection LPGND Loop Ground. Is the system ground reference with respect to VBAT. Normally connected to AGND. 3 VR Voice Receive (input) is the 4 wire analog signal to the device. 4 VREF 5 VEE 6 AGND 7 PD Power Denial (Input). A logic high will isolate the battery voltage to Tip/Ring. 8 VX Voice Transmit (Output) is the 4-wire analog signal from the device. Must be AC coupled. 9 TIP Connects to the “Tip” lead of the telephone line. 10 RING 11 RF 12 VDD 13 RC Relay Control (Input). Active high. 14 RD Open collector sinks current when RC is at logic high. 15 RV Ring Feed Voltage connects to pin 11 (RF) through a normally closed relay. 16 VRLY Voltage Reference (Input) Constant current feed can be adjusted by the input voltage on VREF. This pin can also be grounded for normal 25 mA loop current. Negative Power Supply Voltage (-5 V). Analog Ground (0 V). Connects to the “Ring” lead of the telephone line. Ring Feed (Input) is normally connected to Ring relay for negative battery feed voltage and ringing voltage input. Positive Power Supply Voltage (+5 V). Relay voltage Supply (+5 V). 2 Zarlink Semiconductor Inc. MH88612 Data Sheet Pin Description 17 CD Clamping Diode. Connects to AGND 18 VBAT Negative Battery Feed Supply Voltage (-48 V). 19 CAP Connects external capacitor to ground for ring trip. 20 SHK Switch Hook Detect (Output). Active high. Functional Description The SLIC performs a transformerless 2-wire to 4-wire conversion of the analog signal. The 2-wire circuit is the balanced line going to the subscriber loop, while the 4-wire circuit is the audio signal going to and from devices such as the voice codec or switching circuit. The SLIC also provides a switch hook (SHK) status output which goes high when the telephone is set off-hook. Constant Current Feed The SLIC employs a complex feedback circuit to supply a constant feed current to the line. This is done by sensing the sum of the voltages across the internal feed resistors and comparing it to an input reference voltage (VREF) that determines the constant feed current. If VREF (pin 4) is externally grounded, the constant current is set at 25mA. For a constant current setting between 18mA and 30mA, VREFcan be set between 8.75 Vdc and -6.35 Vdc. The relationship is defined by the equation: ( ( ILOOP = VBAT - VREF mA (+2 mA) 1.89 1.25 Switch Hook Detection When the DC current exceeds an internal threshold level, the switch hook (SHK) will go high. If the loop resistance is so high that VBAT can no longer supply the required amount of loop current as determined by constant current supply circuit, the output of the switch hook (SHK) will go low to indicate that the loop resistance is too high and the line is on hook. Ringing And Ring Trip Detection In Figure 3 a ringing signal (e.g., 90 Vrms and -48 Vdc) is applied to the line by disconnecting pin 15 (RV) from pin 11 (RF), and connecting the ringing voltage at pin 11 (RF) by use of the relay K1. The SLIC can detect an off-hook condition during ringing but there is a large AC component which must be filtered out to give a true off-hook condition at SHK. A 1.0 µF capacitor connected from pin 19 (CAP) to ground will provide adequate attenuation when ringing is applied. Once an off-hook condition has been detected a logic low should be applied to pin 13 (RC) which will deactivate the relay (K1) to disconnect the ringing voltage from pin 11 and reconnect to pin 15. At that time the SLIC will revert to constant current feed operation. For applications requiring Dial Pulse Detection the Capacitor connection to ground should be controlled such that the capacitor is only connected during ringing. During off-hook conditions (closed loop), the capacitor should be switched out. This can be performed using a transistor, relay or system drive output of a codec. Applying AGND to the Ring Trip Filter Control pin as shown in Figure 4 will switch in the filter, whilst removing AGND, (with the switch in a tri-state condition), will switch out the filter. 3 Zarlink Semiconductor Inc. MH88612 Data Sheet For applications using DTMF signalling, the capacitor can be permanently connected to ground. Current Limit The Tip or Ring of the telephone line may accidentally be shorted to ground. In such a case, current will only flow through the feed resistor. This high current will be sensed and reduced by the current limit circuit to a lower value to protect the internal circuitry. Power Denial The power denial function is a feature of the MH88612 which allows for powering down of the subscriber loop. A logic high voltage applied to the power denial input effectively removes the battery voltage from the loop driver circuitry. The resulting ILOOP is negligible and power consumption is minimized. The power denial function is useful for disabling a loop which may have a ground fault. 4 Zarlink Semiconductor Inc. MH88612 R1 K1 11 VBAT ~ + D3 D4 90 VRMS 15 D1 D2 48V 1 2 9 TIP RF Data Sheet MH88612 TF RV VR LPGND VX SHK 10 8 TIP Protection Circuit RING 3 RING PD 13 20 7 RC 16 +5V VRLY C2 14 K1 CAP RD 17 CD VBAT VDD VEE 12 5 18 19 C1 - Q1 + R2 AGND 6 C3 -48V +5V -5V Components List R1 200Ω ± 10%, 1/4W R2 470kΩ R3, R4 10kΩ ± 5%, 1/4W C1 1.0µf, C2, C3 0.1µf ± 5%, 1/4W ± 10%, 25V electrolytic capacitor ± 20%, 50V ceramic de-coupling capacitors D1, D2, D3, D4 Diode rectifier 200V, 1A, IN4003 Q1 General Purpose switching transistor K1 Relay E/M, 5V or 6V 1Form C R3 Protection Circuit - depending on the application the Protection Circuit may need to provide overvoltage and/or over-current protection. In certain circumstances no protection will be required. Figure 3 - Application Circuit 5 Zarlink Semiconductor Inc. R4 RC (Pin 13) MH88612 Data Sheet Absolute Maximum Ratings* Parameter Symbol Min. Max. Units VDD VEE VBAT VRLY VREF -0.3 -15 -60 -0.3 -60 +15 +0.3 +0.3 +40 +15 V V V V V -40 100 °C 2 W 1 DC Supply Voltage LPGND = AGND 2 Storage Temperature TS 3 Package Power Dissipation PD *Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied. Recommended Operating Conditions Characteristics 1 2 3 Operating Supply Voltage Storage Temperature Sym. Min. Typ.‡ Max. Units VDD VEE VREF VBAT VRLY 4.75 -5.25 5.0 -5.0 0 -48 5 5.25 -4.75 V V V V V Adjustable TS -40 100 ×C 2 Storage Temperature To 0 70 °C -60 ‡ Typical figures are at 25°C with nominal supply voltages and are for design aid only 6 Zarlink Semiconductor Inc. -27 Test Conditions MH88612 Data Sheet DC Electrical Characteristics† - Voltages are with respect to GNDA unless otherwise stated. Characteristics 1 Sym. ICC IEE IBAT 5.8 -2.6 PC 210 1410 500 mA mA µA Test Conditions 27 mA VREF = AGND, VBAT = -48V 30 mA Adjustable with Ext. VREF input, VBAT = -48V 1200 Ω 40 mA 0.4 V V IOL IOH 8 -400 mA µA VIL VIH 0.7 V V IIL -50 µA IIH 50 mA 3 Constant Current Line Feed ILoop 23 4 Adjustable Loop Current Range ILoop 18 5 Operating Loop Resistance 6 Ring Ground Over-Current protection 7 Off-Hook Detect Output Low Voltage (On-hook) Output High Voltage (Off-hook) VOL VOH Off-Hook Detect Output Low Current (On-hook) Output High Current. (Off-hook) RC, PD Control Input Input Low Volt (no activation) Input High Volt (activation) RC, PD control Input Input Low Current (no activation) Input high current (activation) PD = Logic High Standby VBAT = -48V Active (Off Hook) Power Consumption 10 Units mW mW 2 9 Max. Supply Current VDD VEE VBAT 8 Typ.‡ Min. 25 RLoop VBAT = -48V @ ILOOP = 18mA, RLOOP includes telephone set Active high logic 2.7 Active high logic 2.0 † DC Electrical Characteristics are over recommended operating supply voltages. ‡ Typical figures are at 25°C with nominal ±5 V supplies and are for design aid only. 7 Zarlink Semiconductor Inc. MH88612 Data Sheet AC Electrical Characteristics Characteristics Sym. Min. 17 1 Ringing Voltage (rms) VRING 2 Ringer Equivalence Number REN 3 Ring Trip Detect time Typ.‡ Max. Units 90 25 Vrms Hz Test Conditions Superimposed on VBAT = -48V 3 200 ms 4 Input AC Impedance 2-wire 600 Ω 5 Input Impedance at VR 100 kΩ 6 Output Impedance at Vx 10 Ω 7 Gain 2-wire to Vx -1.0 dB Gain relative to Gain @ 1 kHz +0.1 Input 3 dBm, 1 kHz across Tip and Ring 300-3400 Hz Gain VR to 2-wire -1.0 dB +0.15 dB Input 1.0 Vrms 1 kHz at VR ZLoad = 600 Ω 300 - 3400 Hz 8 Zin Gain relative to Gain @ 1 kHz 9 2-wire Return Loss over 300-3400 Hz 10 Transhybrid Loss 11 Longitudinal to Metallic Balance over 300-3400 Hz 12 Total Harmonic Distortion at VX RL 20 30 dB Input 0.5 Vrms , 1 kHz across Tip and Ring, ZLoad = 600 Ω THL 20 30 dB Input 0.5 Vrms, 1kHz at VR ZLoad= 600 Ω 50 55 dB Input 0.5 Vrms Input 3 dBm, 1 kHz across Tip and Ring, THD at Tip and Ring 13 Common Mode Rejection Ratio 2-wire to Vx 14 Idle channel Noise 15 Power supply rejection ratio VDD VEE VBAT CMRR 40 0.1 1.0 % 0.1 1.0 % 50 Nc 12 Input 1.0 Vrms 1 kHz at VR dB Input 0.5Vrms, 1 kHz dBrnC C @ & VX Message PSRR dB dB dB 26 26 26 ‡ Typical figures are at 25°C with nominal ±5V supplies and are for design aid only. 8 Zarlink Semiconductor Inc. 1 VPP ripple, 1 kHz on VDD/VEE/VBAT,measure at VX and across Tip & Ring MH88612 0.08 Max 0.12 Max (2.03 Max) (3.05 Max) Data Sheet 2.120 Max (53.85 Max) 0.6 Max (15.24 Max) 1 0.180 + 0.020 (4.57 + 0.51) 0.020 + 0.005 (0.5 + 0.13) 0.010 + 0.002 (0.25 + 0.05) *0.05 + 0.02 (1.25 + 0.51) * 0.100 + 0.010 (2.54 + 0.25) Notes: 1) Not to scale 2) Dimensions in inches. (Dimensions in millimetres) 3) Pin tolerances are non-accumulative. 4) Recommended soldering conditions: wave soldering max. temp: 260°C for 10 secs. * Dimensions to centre of pin. Figure 4 - Mechanical Data 9 Zarlink Semiconductor Inc. For more information about all Zarlink products visit our Web Site at www.zarlink.com Information relating to products and services furnished herein by Zarlink Semiconductor Inc. or its subsidiaries (collectively “Zarlink”) is believed to be reliable. However, Zarlink assumes no liability for errors that may appear in this publication, or for liability otherwise arising from the application or use of any such information, product or service or for any infringement of patents or other intellectual property rights owned by third parties which may result from such application or use. Neither the supply of such information or purchase of product or service conveys any license, either express or implied, under patents or other intellectual property rights owned by Zarlink or licensed from third parties by Zarlink, whatsoever. Purchasers of products are also hereby notified that the use of product in certain ways or in combination with Zarlink, or non-Zarlink furnished goods or services may infringe patents or other intellectual property rights owned by Zarlink. This publication is issued to provide information only and (unless agreed by Zarlink in writing) may not be used, applied or reproduced for any purpose nor form part of any order or contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this publication are subject to change by Zarlink without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific piece of equipment. It is the user’s responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or data used is up to date and has not been superseded. Manufacturing does not necessarily include testing of all functions or parameters. These products are not suitable for use in any medical products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to Zarlink’s conditions of sale which are available on request. Purchase of Zarlink’s I2C components conveys a licence under the Philips I2C Patent rights to use these components in and I2C System, provided that the system conforms to the I2C Standard Specification as defined by Philips. Zarlink, ZL, the Zarlink Semiconductor logo and the Legerity logo and combinations thereof, VoiceEdge, VoicePort, SLAC, ISLIC, ISLAC and VoicePath are trademarks of Zarlink Semiconductor Inc. TECHNICAL DOCUMENTATION - NOT FOR RESALE