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| (R) MH88628 Central Office SLIC Preliminary Information Features * * * * * * * * * * * * Programmable gain, network balance and impedance Transformerless 2-4 wire conversion Constant current with constant voltage fallback for long loop capability Pin compatible with MH88632, MH88620 and MH88628 Unbalanced detection (Tip, Ring ground sensing) Auto ring trip with zero crossing On-Hook transmission (ANI) capability Compatible with requirements of CCITT, DOC/FCC and CSA/UL Excellent power dissipation (SIL vertical mounting) 12/16kHz meter pulse injection control Solid State TIP/RING reversals Ringing amplifier MH88628 ISSUE 5 April 1995 Ordering Information 40 Pin SIL Package 0C to 70C Applications * * * On/Off Premise PBX Line Cards DID (Direct Inward Dial) Line Cards Central Office Line Cards Description The Mitel MH88628 SLIC provides all of the functions required to interface 2-wire off premise subscriber loops to a serial TDM, PCM, switching network of a modern PBX. The MH88628 is manufactured using thick-film hybrid technology which offers high voltage capability, reliability and high density resulting in significant printed circuit board area savings. A complete C.O. line card can be implemented with very few external components. VBat LGND LCA VDD VEE AGND RING RF1 RF2 TIP TF1 TF2 Matched Feed Resistors Driver Circuitry and Speech Circuit Loop Current Set Switch-hook Threshold Set Ring Filter Switch-hook Detect SHK NS UD Unbalanced Detection Impedance Network 2-4 Wire Conversion N1 N2 NATT VRLY RNGD RD Decoder Circuit Ringing Amplifier External Signal Input Gain Adjust SEL1 SEL2 ACRI DCRI ESI ESE Z900 Z600 Z1 Z2 GRX1 GRX0 RX GTX1 GTX0 TX Figure 1 - Functional Block Diagram 2-199 MH88628 TIP RING TF1 TF2 RF1 RF2 LGND LCA VBat DCRI RGND VRLY RD SEL1 SEL2 ESI ESE AGND NATT N1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 N2 Z900 Z1 Z2 TX RX GTX0 GTX1 GRX0 GRX1 ACRI Z600 NS SHK UD IC IC IC VEE VDD Preliminary Information 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Figure 2 - Pin Connections Pin Description Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Name TIP RING TF1 TF2 RF1 RF2 LGND LCA VBat DCRI RGND VRLY RD SEL1 SEL2 ESI ESE AGND NATT Description Tip Lead. Connects to the "Tip" lead of subscriber line. Ring Lead. Connects to the "Ring" lead of the subscriber line. Tip Feed 1. Access point for balanced ringing. Normally connects to TF2. Tip Feed 2. Access point for balanced ringing. Normally connects to TF1. Ring Feed 1. Access point for balanced ringing. Normally connects to RF2. Ring Feed 2. Access point for balanced ringing. Normally connects to RF1. Battery Ground. VBat return path. Connected to system's energy dumping ground. Current Limit Set (Input). The current limit is set by connecting an external resistor to ground. For 30mA default current, this pin is tied to GND. Battery Voltage. Typically -48Vdc is applied to this pin. DC Ringing Voltage Input. A continuous 120Vdc is applied to this input. Relay Driver Ground Connection. Relay Supply Voltage Connection. Ring Drive (Output). Connects to ring relay coil. Select 1 (Input). Refer to Table 5 Select 2 (Input). Refer to Table 5. External Signal Input. 12/16kHz meter pulse input. External Signal Enable. Applies the external signal to the line. Analog Ground. VDD and VEE return path. Network Balance AT+T Node. Connects to N1 for a network balance impedance of AT&T compromise (350 + 1k // 210nF); the device's input impedance must be set to 600. This node is active only when NS is at logic high. This node should be left open circuit when not used. 2-200 Preliminary Information Pin Description (Continued) Pin # 20 Name N1 Description MH88628 Network Balance Node 1(Input). 0.1 times the impedance between pins N1 and N2 must match the device's input impedance, while 0.1 times the impedance between pins N1 and AGND is the device's network balance impedance. This node is active only when NS is at logic high. This node may be terminated when not used (i.e., NS at logic low). Network Balance Node 2 (Output). See N1 for description. Line Impedance 900 Node. Connects to Z1 for a line impedance of 900. This node should be left open circuit when not used. Line Impedance Node 1 (Input). 0.1 times the times the impedance between pins Z1 and Z2 is the device's line impedance. This node must always be connected. Line Impedance Node 2 (Output). 0.1 times the times the impedance between pins Z1 and Z2 is the device's line impedance. This node should be left open circuit when not used. Transmit (Output). 4-Wire (AGND) referenced audio output. Receive (Input). 4-Wire (AGND) referenced audio input. Transmit Gain Node 0. Connects to GTX1 for 0dB transmit gain. Transmit Gain Node 1. A resistor to AGND provides transmit gain adjustment. Receive Gain Node 0. Connects to GRX1 for 0dB gain. Receive Gain Node 1. A resistor to AGND provides receive gain adjustment. AC Ringing Voltage Input. A 1.5Vrms 20Hz signal is applied to this input. Line Impedance 600 Node (Output). Connects to Z1 for a line impedance of 600. This pin should be left open circuit when not used. Network Balance Setting (Input). The logic level at NS selects the network balance impedance. A logic 0 enables an internal balance equivalent to the input impedance (Zin). While a logic 1 enables an external balance 0.1 times the impedance between pins N1 and AGND balanced to 0.1 times the impedance between pins N1 and N2. The impedance between N1 and N2 must be equivalent to 10 times the input impedance (Zin). Off-Hook Indication (Output). A logic low output indicates when the subscriber equipment has gone Off-Hook. Unbalance Detect (Output). A log IC low output indicates when the DC current flow in the Tip and Ring leads is unbalanced, indicating that the subscriber equipment has grounded the Ring lead. Internal Connection. These pins are internally connected and must be left open Negative Supply Voltage. -5V dc. Positive Supply Voltage. +5V dc. 21 22 23 24 25 26 27 28 29 30 31 32 33 N2 Z900 Z1 Z2 TX RX GTX0 GTX1 GRX0 GRX1 ACRI Z600 NS 34 35 SHK UD 36,37,38 IC VEE VDD 39 40 2-201 MH88628 Absolute Maximum Ratings* Parameter 1 Supply Voltage Sym VBat VDD VEE VDCRI TS Min +0.3 -0.3 +0.3 -0.3 -40 Max 65 6 -6 140 +125 Units V V V V C Preliminary Information Comments With respect LGND 2 Storage Temperature * Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied. Recommended Operating Conditions Parameter 1 Supply Voltage Sym VBat VDD VEE TOP Min -44 4.75 -4.75 0 Typ* -48 +5.0 -5.0 20 90 17 VDCRI 110 120 33 130 Max -60 5.25 -5.25 70 Units V V V C Vrms Hz Vdc Comments 2 3 Operating Temperature AC Ring Generator Voltage Frequency 4 DCRI Input DC Voltage * Typical figures are at 25 C with nominal + 5V supplies for design aid only. DC Electrical Characteristics Characteristics 1 Operating Loop Current Sym ILoop ILoop ILoop ILoop IBat IBat IDD IEE 3 4 SHK UD 5 6 SEL1 SEL2 ESE NS Low level Output Voltage High Level Output Voltage Low Level Input Voltage High Level Input Voltage High Level Input Current Low Level Input Current VOL VOH VIL VIH IIH IIL 0.5 3.7 0.8 2.4 20 20 V V V V A A VIH=5.0V VIL=0.0V IOL = 400A IOH= 40A Power Dissipation PDO PD1 Min 16 30 2 32 2 25 25 2 300 Typ* 45 Max Units mA mA mA mA mA mA mA mA W mW Test Conditions RLoop=0 2300 VBat =-48V RLoop=0, LCA GND RLoop =0 (off Hook), LCA=GND RLoop = open (OnHook) On-hook or Off-Hook On-Hook or Off-Hook Active Standby/Idle Var in loop current from nominal 2 Operating Currents DC Electrical Characteristics are over recommended operating conditions unless otherwise stated. * Typical figures are at 25C with nominal +5V supplies and are for design aid only. 2-202 Preliminary Information AC Electrical Characteristics Characteristics 1 2 3 4 TX Gain RX Gain Ringing Capability On-Hook Transmission Signal Input Level Gain External Signal Output Level 1.75 Sym Min Typ* 0 0 5 2.0 6 2.25 Max Units dB dB REN Vrms dB Vrms MH88628 Test Conditions externally adjustable externally adjustable VBat=-48V T-R load = 10k min. VBat= -48V, T-R load= 200 LCA=0V, Zo-600, Gain=0dB Dial Pulse Detection 5 6 7 8 9 SHK Rise Time Fall time 2-Wire Termination Impedance Off-Hook Detect Threshold 2-Wire Return Loss tR tF 1 1 600/ 900 10 20 20 20 58 53 40 ms ms Selectable mA dB dB dB dB dB mA 300 to 500Hz 500 to 2500Hz 2500 to 3400Hz 200-1000Hz 1kHz - 3k4Hz 20mA per lead 10 Longitudinal Balance Longitundinal to Metallic Longitudinal Current Capability Idle channel Noise Rx to T-R T-R to Tx NCR NCX THL IUB 11 12 8 12 22 40 10 4 90 17 100 +0.1 +0.05 33 dBrnC dBrnC dB mA dBm Vrms Hz ms dB dB dB 0dB at T-R, 1kHz 300-3400Hz 1kHz, 100mVpp T-R=600, VBat=-48V 200-3400Hz 13 14 15 16 17 18 19 20 21 Transhybrid Loss Unbalanced Detect Threshold Analog Signal Overload Level At Tip and Ring Ringing Signal Voltage Ringing Frequency Ring Trip Delay Absolute Gain, Variation Relative Gain, reference to 1kHz Power Supply Rejection Ratio PSRR VBat 24 VDD 24 VEE 24 * Typical figure are at 25C with nominal +5V supplies and are for design aid only. AC Electrical Characteristics are over recommended operating conditions unless otherwise stated. Notes: Impedance set by external network of 600 or 900 default. External network for test purposes consists of 2200 + 8200 // 11.5nF between pins Z1 and Z2, the equivalent Zin has 1/10th the impedance and is equivalent o 220+820 // 115nF. Test condition uses a Zin value of 600, 900 and the above external network. Test conditions use a transmit and receive gain set to 0dB default and a Zin value of 600 unless otherwise stated. "Ref" indicates reference impedance which is equivalent to the termination impedance. "Net" indicates network balance impedance. Refer to Table 1, 2 for TX, RX gain adjustment. 2-203 MH88628 Functional Description The SLIC uses a transformerless electronic 2-wire to 4-wire conversion which can be connected to a Codec to interface the 2 wire subscriber loops to a time division multiplexed (TDM) pulse code modulated (PCM) digital switching network. For analog applications, the Tx and Rx of the 2-4 wire converter can be connected directly to an analog crosspoint switch such as the MT8816. Powering of the line is provided through precision battery feed resistors. The MH88628 also contains control, signalling and status circuitry which combines to provide a complete functional solution which simplifies the manufacture of line cards. This circuitry is illustrated in the functional block diagram in Fig. 1. The MH88628 is designed to be pin compatible with Mitel's MH88632 and MH88625. This allows a common PCB design with common gain, input impedance and network balance. Preliminary Information Loop Current Setting The MH88628 SLIC is a constant current with constant voltage fallback design. This design feature provides for long loop capability regardless of the constant current setting. Refer to Graph 1. The LCA (Loop Current Adjust) pin is an input to an internal resistor divider network which generates a bias voltage. The loop current is proportional to this voltage. The loop current can be set between 20 and 45mA by various connections to the LCA pin as illustrated in Table 5 and Figure 8. The loop current during a fault condition will be limited to a safe level. Primary over-current protection is inherent in the current limiting feature of the 200 battery feed resistors. Refer to Graph 1. Receive and Transmit Audio Path The audio signal of the 2-wire side is sensed differentially across the external 200 feed resistors and is passed on to a second differential amplifier stage in the 2W/4W conversion block. This block sets the transmit gain on the 4-wire side and cancels signals originating from the receive input before outputting the signal. Approvals FCC part 68, CCITT, DOC CS-03, UL 1459, CAN/ CSA 22.2 No.225-M90 and ANSI/EIA/TIA-464-A are system level safety standards and performance requirements. As a component of a system, the MH88628 is designed to comply with the applicable requirements of these specifications. Programmable Transmit and Receive Gain Transmit Gain (Tip-Ring to Tx) and Receive Gain (Rx to Tip-Ring) are programmed by connecting external resistors (RRX and RRT) from GRXI to AGND and from GTX1 to AGND as indicated in Figure 3 and Tables 1 and 2. The programmable gain range is from -12dB to +6dB; this wide range will accommodate any loss plan. Alternatively, the default Receive Gain of 0dB and Transmit Gain of 0dB can be obtained by connecting GRX0 to GRX1 and GTX0 to GTX1. In addition, a Receive gain of +6dB and Transmit Gain of +6dB can be obtained by not connecting resistors RRX and RTX. For correct gain programming, the MH88628's Tip-Ring impedance (Zin) must match the line termination impedance. For optimum performance, resistor RRX should be physically located as close as possible to the GRX1 input pin, and resistor RTX should be physically located as close as possible to the GTX1 input pin. Battery Feed The loop current for the subscriber equipment is sourced through a pair of matched 200 resistors connected to the Tip and Ring. The two wire loop is biased such that the Ring lead is 2V above VBat (typically -46V) and the Tip lead is 2V below LPGD (typically -2V) during constant voltage, constant current mode. The SLIC is designed for a nominal battery voltage of -48Vdc and can provide the maximum loop current of 45mA under the condition. The MH88628 is designed to operate down to a minimum of 16mA dc, with a battery voltage of -44V. The Tip and Ring output drivers can operate within 2V of VBat and LGND rails. This permits a maximum loop range of 2300. 2-204 Preliminary Information MH88628 70 60 50 40 ILoop (mA) 30 20 10 0 1k RLoop () 2k Constant Current Region Constant Voltage Region Graph 1 - ILoop/RLoop Characteristics Two wire Port Termination Impedance The AC termination impedance of 600 or 900, of the 2W port, is set using active feedback paths to give the desired relationship between the line voltage and the line current. The loop current is sensed differentially across the two feed resistors and converted to a single ended signal. This signal is fed back to the Tip/Ring driver circuitry such that impedance in the feedback path gets reflected to the two wire port. The MH88628's Tip-Ring impedance (Zin) can be set to 600, 900 or to a user selectable value. Thus, Zin can be set to any international requirement. The connection to Z1 determines the input impedance. With Z1 connected to Z600, the line impedance is set to 600. With Z1 connected to Z900, the line impedance is set to 900. A user defined impedance can be selected which is 0.1 times the impedance between Z1 and Z2. For example, with 2200 in series with 11.5nF in parallel with 8200, all between Z1 and Z2, the devices line impedance will be 220 in series with 115nF in parallel with 820. See Table 3 and Figures 4 & 5. user defined network balance impedance is selected which is 0.1 times the impedance between N1 and AGND. For example, with 2200 in series with 11.5nF in parallel with 8200, all between N1 and AGND, and NS at logic high, the devices network balance impedance is 220 in series with 115nF in parallel with 820; the impedance between N1 and N2 must be equivalent to 10 times the input impedance (Zin). In addition, with NS at logic high, an AT&T network balance impedance can be selected by connecting NATT to N1; in this case, no additional network is required between N1 and N2. See Table 4 and Figure 6. 12/16kHz Meter Pulse The MH88628 provides control of an external signal path to the driver. A 12/16kHz continuous signal can be applied to the ESI pin. Control of the ESE input allows the metering signal to be transmitted to the line. Unbalanced Detection The Unbalanced Detect (UD) pin goes low when the DC current through the two battery feed resistors is unbalanced i.e., when the average DC current into the Ring lead exceeds the current flow out of the Tip lead (indicating that the Ring lead has been grounded). When the SLIC is interfaced to ground start subscriber equipment during the idle state, the UD output is monitored for indication of the subscribers Ring Ground signal. The maximum loop current supplied by the feed circuitry under this condition is limited. Network Balance Transhybrid loss is maximized when the line termination impedance and SLIC network balance are matched. The MH88628's network balance impedance set can be set to Zin, AT&T (350 + 1k //210nF) or to a user selectable value. Thus, the network balance impedance can be set to any international requirement, A logic level control input NS selects the balance mode. With NS at logic low, an internal network balance impedance is matched to the line impedance (Zin). With NS at logic high, a 2-205 MH88628 Longitudinal Balance The longitudinal balance specifies the degree of common mode rejection in the 2 to 4 wire direction. Precision laser trimming of internal resistors in the hybrid ensures good overall longitudinal balance. The interface circuitry can operate in the presence of induced longitudinal currents of up to 40mA at 60Hz. Preliminary Information Ring Trip Detection The interface permits detection of an Off-Hook condition during the ringing. If the subscriber set goes Off-Hook when the ringing signal has been applied, the DC loop current flow will be detected within approx. 100msecs and the SHK output will go low. The ring relay is automatically disabled by the internal hardware. Off-Hook and Dial Pulse Detection The SHK pin goes low when the DC-loop current exceeds a specified level. The threshold level is internally set by the bias voltage of the switch-hook detect circuitry. Dial pulse can be detected by monitoring the interruption rate at the SHK pin. These dial pulses would be debounced by the system's software. Control Decode The different modes of operation are selected by decoding the SEL1 and SEL2 inputs (see Table 5). DTMF The DTMF tones are transmitted and received at the 4-wire port. MH88628 Z Transmit Gain: Z + TX 25 (Tip-Ring to Tx) AV= -20log 5k [ 0.5 + RTX ] 10k GTX1 10k GTX0 28 27 RTX RTX = Example 5k 10(-AV/20)-0.5 RTX=38k; AV= +4dBV Z + 10k RX 26 GRX1 GRX0 10k 30 RRX Receive Gain: (RX to Tip-Ring) AV= -20log 5k [ 0.5 + RRX ] 5k 10 (-AV/20) Example: RRX=4.6k; AV= -4dBV -0.5 29 RRX = Figure 3 - Gain Programming with External Components 2-206 Preliminary Information MH88628 Z2 24 NC Z2 24 NC MH88628 Z1 23 MH88628 Z1 23 22 Z900 22 NC Z900 32 32 Z600 Z600 NC Input impedance (Zin) set to 600 Note: Make connection between Z1 and other points as short as possible Input Impedance (Zin) set to 900 Figure 4 - Input Impedance (Zin) Settings with Zin equal to 600 or 900 Z2 24 10 x Zin 10 x Z in RP Z2 CP MH88628 Z1 23 22 Z900 Z1 RS 1 Z600 32 Zin = 0.1 x [ RS + 1/RP + (S x CP) ] where S = j x w and w = 2 x x f Example: Notes: 1) The 10xZin network must be set to 10 x the desired input impedance (Zin). 2) The network balance must be set to the desired network balance. See section on network balance. 3) Make connection between Z1 and component as short as possible. If RS = 2200, RP = 8200, CP= 11.5nf Then the input impedance (Zin) is 220 in series with 820 in parallel with 115nF. Figure 5 - Input Impedance (Zin) Settings with Zin not equal to 600 to 900 2-207 MH88628 Preliminary Information N2 21 N2 21 MH88628 N1 20 MH88628 20 N1 19 NATT 19 NATT NS 33 NS 33 VDD Network balance is set to the input Impedance (Zin) Note: Make connection between Z1 and other points as short as possible Network balance is set to the AT&T compromise network (350 + 1000 // 210nF) impedance. The input impedance must be set to 600W. Figure 6 - Network Balance Setting with NETBAL equal to Z in or AT&T 10 x Zin N2 21 10 x Zin RP N2 MH88628 N1 20 10 x NETBAL CP 19 NATT N1 RS ZNETBAL = 0.1 x 33 NS VDD where S = j x w and w = 2 x x f [ RS + 1/RP + (S x CP) ] 1 Notes: 1) The 10xZin network must be set to 10 x the desired input impedance (Zin). 2) The network balance must be set to the desired network balance. See section on network balance. 3) Make connection between Z1 and component as short as possible. Example: If RS = 2200, RP = 8200, CP= 11.5nf Then the network balance impedance (ZNETBAL) is 220 in series with 820 in parallel with 115nF. Figure 7 - Network Balance Setting with NETBAL not equal to Zin or AT&T 2-208 Preliminary Information Tables 1 & 2: Transmit and Receive Gain Programming Transmit Gain (dB) +6.0 +4.0 +3.7 0.0 -3.0 -6.0 -12.0 Receive Gain (dB) +6.0 0.0 -3.0 -3.7 -4.0 -6.0 -12.0 RTX Resistor Value () No Resistor 38.3k 32.4k GTX0 to GTX1 5.49k 3.32k 1.43k RRX Resistor Value () No Resistor GRX0 to GRX1 5.49k 4.87k 4.64k 3.32k 1.43k Notes Notes MH88628 Results in 0dB overall gain when used with Mitel A-law codec (i.e. MT8965) Results in 0dB overall gain when used with Mitel -law codec (i.e. MT8964) Results in 0dB overall gain when used with Mitel A-law codec (i.e. MT8965) Results in 0dB overall gain when used with Mitel -law codec (i.e. MT8964) Note 1: See Figures 3 and 4 for additional details. Note 2: Overall gain refers to the receive path of PCM to 2-wire, and transmit path of 2-wire to PCM. Table 3: Input Impedance Settings Z2 NA NA Z1 Connect Z1 to Z9000 Z600 NA NA Z900 NA Connect Z1 to Z900` NA Resulting input impedance (Zin) 600 900 0.1 x impedance between Z1 & Z2 Connect Z1 to Z600 Connect network from Z1 to Z2 Note 1: NA indicates high impedance (10k) connection to this pin does not effect the resulting network balance. Note 2: See Figure 4 & 5 for Application Circuits. Table 4: Network Balance Settings NS (Input) Low High High N2 NA NA N1 NA Connect N1 to NATT NA 0.1 x impedance between N1 & N2 NATT NA Resulting input impedance (Zin) Equivalent to Zin AT&T compromise (350 + 1k // 210nF) Zin must be 600 Connect network from N1 to AGND equivalent to 10 x NETBAL. Connect network from N1 to N2 equivalent to 10 x Zin. Note 1: NA indicates high impedance (10k) connection to this pin does not effect the resulting network balance. Note 2: Low indicates Logic Low. Note 3: See Figures 6 and 7 for Application Circuit. 2-209 MH88628 Preliminary Information +5V R LCA LCA R -5V LCA 8a 8b 8c Loop Current Setting Figure 8 - Loop Current Setting High Voltage capability Inherent in the thick-film process is the ability of the substrate to handle high voltage. The standard Mitel thick-film process provides dielectric strengths of greater than 1000VAC or 1500VDC. The thick-film process allows easy integration of surface mount components such as the high voltage bi-polar power transistor line drivers. This allows for simplier, less elaborate and less expensive protection circuitry required to handle high voltage transients and fault conditions caused by lightning, induced voltages and power line crossings. Loop Length The MH88628 can accommodate loop length of up to 2300 minimum (including the subscriber equipment). This corresponds to approximately 8km using 26AWG twisted pair or 15km using 24AWG twisted pair. Central Office Operation The MH88628 can be configured for ground start C.O. applications with the addition of Q1, D1 and K2, as shown in Figure 9. Ground start requires control of the Tip lead to remove battery ground from subscriber loop. For loop start applications, control of the Tip lead is not required. C.O's perform Tip/Ring reversals to indicate that a tool call has been dialled. The Tip/ring reversal can indicate a toll diversion signal. On-hook Transmission The MH88628 provides for on-hook transmission which supports features such as Automatic Numbers Identification (ANI). The (ANI) information is a FSK signal originating from and sent by the C.O. during the off period of the ringing voltage being sent to the subscribers set. The signal is present during the off period between the first and second ring. The subscribers set decodes the FSK signal and displays the calling party's number. Internal Ringing Amplifier Operation The MH88628 offers an on-board ringing amplifier. A 1.5 VRMS, 20Hz signal is amplified internally and applied to TIP and RING leads in a balanced configuration. A +120Vdc supply are applied continuously to the MH88628. The decode signals on SEL1 and SEL2 enable the ringing signal to the TIP and RING when required. TIP Disable A relay driver, controlled by SEL1 and SEL2, is provided to drive a relay which can be used to disable the TIP line when the MH88628 is used for a ground start central office interface. 2-210 Preliminary Information MH88628 -VBat SYSTEM GROUND +5V VDD VBat RX GRX0 VR VX CODEC VEE MH88628 GRX1 LCA -5V AGND TX GTX0 TF1 GTX1 TF2 SHK P R O T E C T I O N RF1 K1B ACRI +5V K1 RF2 VRLY DCRI 1.5VRMS 20Hz Source TIP UD Z1 Z600 SEL1 RING SEL2 ESE 12/16kHz ESI Metering Source LINE CONTROLLER LOGIC + 120VDC Supply RGND NS RD Figure 9 - OPS SLIC Configuration Applications Circuit - Normal Ringing Graph 2 - Loop Current Setting 65mA 50 ILoop/mA To -5V 40 (/10) O/C LCA 35.3mA To +5V (/10 + 10mA) 30 LCA = 0V 28.48m 20 10K 100K 1M R(LCA) 2-211 MH88628 Table 5: Control Decode Table Mode 1 2 3 4 Condition Normal Operation Apply internal balanced ringing Reverse TIP and RING Enable Relay Driver SEL1 0 1 0 1 Preliminary Information SEL:2 0 0 1 1 Table 6: Loop Current Setting Loop Current 20 25 30 35 40 45 Ref. Fig # 8a 8a 8a 8c 8b 8b LCA Pin Connection Connect 10k from LCA to +5V Connect 22k from LCA to +5V Connect 36k from LCA to +5V LCA open circuit Connect 24k to -5V Connect 10k from LCA to -5V PRIMARY MDF PROTECTION T HEAT COIL SECONDARY PROTECTION F1 R1 T MH88628 PRO1 GAS TUBE F2 R2 R HEAT COIL R SUGGESTED COMPONENTS: F1, F2 1A, 250VAC, SLO-BLOW LITTLEFUSE 230 2AG R1, R2, 10, 1000V, 1/2W RESISTOR (FLAME RATED) PRO1 SOLID STATE TRANSIENT SUPPRESSOR, EG TISP2300L, P2703AB F1, R1 AND F2, R2 MAY BE FUSIBLE RESISTORS OR PTCs Figure 10 - Typical Protection Circuit 2-212 Preliminary Information MH88628 Side View 0.080 Max (2.0 Max) 4.20 + 0.020 (50.8 + 0.5) 0.80+0.03 (20.3+0.76) 1234 39 40 0.010 + 0.002 (0.25 + 0.05) 0.12 Max (3.1 Max) 0.05 + 0.01 (1.3 + 0.5) Notes: 1) Not to scale 2) Dimensions in inches). 3) (Dimensions in millimetres). *Dimensions to centre of pin & tolerance non accumulative. * 0.25 + 0.02 (6.35 + 0.05) 0.020 + 0.05 (0.51 + 0.13) * * 1 2 3 0.175 + 0.02 (4.445 + 0.5) 0.100 + 0.10 (2.54 + 0.13) Figure 11 - Mechanical Data 2-213 MH88628 Notes: Preliminary Information 2-214 |
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