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MH88625
DID/OPS 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 and MH88628 Unbalance detection (Tip, Ring ground sensing) Auto ring trip 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 MH88625
ISSUE 6
April 1995
Ordering Information 40 Pin SIL Package 0C to 70C
Description
The Mitel MH88625 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 MH88625 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 line card can be implemented with very few external components.
Applications
* * * On/Off Premise PBX Line Cards DID (Direct Inward Dial) Line Cards Central Office Line Cards
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 N1 N2 NATT
UD
Unbalance Detection Impedance Network
2-4 Wire Conversion
RNGC RGND VRLY
Ring Relay Driver
Tip/Ring Reversal
External Signal Input
Gain Adjust
RRD
REVC
ESI
ESE
Z900 Z600 Z1
Z2
GRX1 GRX0 RX GTX1 GTX0 TX
FIgure 1 - Functional Block Diagram
2-183
MH88625
TIP RING TF1 TF2 RF1 RF2 LGND LCA VBat IC RGND VRLY RRD RNGC REVC 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 IC Z600 NS SHK UD IC IC IC VEE VDD 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
Preliminary Information
Figure 2 - Pin Connections
Pin Description
Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Name TIP RING TF1 TF2 RF1 RF2 LGND LCA VBat IC RGND VRLY RRD RNGC 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. Internal Connection. This pin is internally connected and must be left open. Relay Driver Ground Connection. Relay Supply Voltage Connection. Ring Relay Drive (Output). Connects to ring relay coil. Ring Relay control (Input). A logic low enables the Ring Relay Drive (RRD) output which activates the Ring Relay. The internal auto ring trip circuitry de-activates the relay drive output upon detection of switch-hook. Reversal Control (Input). A logic high reverse the internal Tip and Ring connections. External Signal Input. 12/16kHz meter pulse input. External Signal Enable. 12/16kHz meter pulse enable. Analog Ground. VDD and VEE return path.
15 16 17 18
REVC ESI ESE AGND
2-184
Preliminary Information
Pin Description (Continued)
Pin # 19 Name NATT Description
MH88625
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. 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. Connects to a resistor to AGND for transmit gain adjustment. Receive Gain Node 0. Connects to GRX1 for 0dB gain. Receive Gain Node 1. Connects to a resistor to AGND to receive gain adjustment. Internal Connection. This pin is internally connected and must be left open. 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.
20
N1
21 22 23 24 25 26 27 28 29 30 31 32 33
N2 Z900 Z1 Z2 TX RX GTX0 GTX1 GRX0 GRX1 IC Z600 NS
34
SHK
35
UD
36,37,38
IC VEE VDD
39 40
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MH88625
Absolute Maximum Ratings*
Parameter 1 Supply Voltage Sym VBat VDD -VEE TS Min +0.3 -0.3 +0.3 -40 Max 65 6 6 +125 Units 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 20 Typ* -48 +5.0 -5.0 0 Max -60 5.25 -5.25 70 Units V V V C Comments
2
Operating Temperature
* Typical figures are at 25 C with nominal + 5V supplies for design aid only.
DC Electrical Characteristics
Characteristics 1 Operating Loop Current Var in loop current from nominal 2 Operating Currents Sym ILoop ILoop ILoop ILoop IBat IBat IDD IEE 3 4 5 6 SHK UD ESE NS ESE NS Power Dissipation Low Level Output Voltage High Level Output Voltage Low Level Input Voltage High Level Input Voltage High Level Input Current Low Level Input Current PD0 PD1 VOL VOH VIL VIH IIH IIL 3.7 0.8 2.4 20 20 Min 16 30 +4 32 2 25 25 2 300 0.5 Typ* Max 45 Units mA mA mA mA mA mA mA mA W mW V V V V A A VIH=5.0V VIL=0.0V 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 IOL = 400A IOH= 40A
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.
2-186
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
MH88625
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 3400Hz 20mA per lead
10
Longitudinal Balance Longitundinal to Metallic Metallic to Longitudinal 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 VBat VDD VEE
PSRR 24 24 24
AC Electrical Characteristics are over recommended operating conditions unless otherwise stated. * Typical figure are at 25C with nominal +5V supplies and are for design aid only. 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.
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MH88625
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 MH88625 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 MH88625 is designed to be pin compatible with Mitel's MH88632 and MH88628. This allows a common PCB design with common gain, input impedance and network balance.
Preliminary Information
Loop Current Setting
The MH88625 SLIC provides a constant current with constant voltage fallback. 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 graph 2 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-464A are system level safety standards and performance requirements. As a component of a system, the MH88625 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 MH88625'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 MH88625 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.
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Preliminary Information
MH88625
70 60 50
ILoop (mA)
40 30 20 10 0
Constant Current Region
Constant Voltage Region
1k
2k
RLoop ()
Graph 1 - I Loop/R Loop 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 MH88625'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.
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 MH88625 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 MH88625'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 user defined network balance impedance is selected which is 0.1 times the impedance between N1 and
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MH88625
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
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.
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 approximately 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.
MH88625
Z
TRANSMIT GAIN: (Tip-Ring to Tx) 5k AV = - 20 log 0.5 + ---------- RTX TX 25 5k RTX = -------------------------------- - AV GTX1 10k GTX0 10 Example: RTX = 38k; AV = +4dB
---------- 20
Z 10k
+
28 27
RTX
- 0.5
Z
RECEIVE GAIN: (RX to Tip-Ring)
+
Z 10k RX
26
RRX
5k AV = - 20log 0.5 + ---------- RRX 5k RTX = -------------------------------- - AV 10 Example: RRX = 4.6k; AV = -4dB
---------- 20
GRX1 30 GRX0 10k
29
- 0.5
Figure 3 - Gain Programming with External Components
2-190
Preliminary Information
MH88625
MH88625
Z2 24 NC
MH88625
Z2
24
NC
Z1
23
Z1
23
22 Z900 22 NC Z900
32 Z600
Z600
32
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
MH88625
Z2 24 10 x Zin 23 Z1 Z1 RS RP
Z2
CP
22 Z900
Z600
32
Zin = 0.1 x
(RS + 1) 1/RP + S x CP
where S = j x w and w = 2 x x f
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 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
2-191
MH88625
Preliminary Information
MH88625
N2
21
MH88625
21 N2
N1
20 N1
20
19 NATT
NATT
19
33 NS 33 NS 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
MH88625
N2 21 10 x Zin N2 N1 20 10 x NETBAL 19 NATT CP RP
N1 RS
(RS + 1) NS 33 VDD ZNetbal = 0.1 x 1/RP + S x CP
where S = j x w and w = 2 x x f
Notes:
Example: 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 7 - Network Balance Setting with NETBAL not equal to ZNetbal or AT&T
2-192
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
MH88625
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 Z900 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 Applications Circuits.
Table 4: Network Balance Settings. NS (Input) Low High N2 NA NA Connect N1 to NATT High Connect network from N1 to AGND equivalent to 10 x NETBAL. Connect network from N1 to N2 equivalent to 10 x Zin. NA 0.1 x impedance between N1 & N2 N1 NA NATT NA Resulting input impedance (Zin) Equivalent to Zin AT&T compromise (350 + 1k // 210nF) Zin must be 600
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.
2-193
MH88625
Preliminary Information
+5V
MH88625
R
MH88625
MH88625
MH88625
LCA
LCA
LCA R -5V
LCA
8a
8b
8c
8d
Figure 8 - Loop Current Setting (See Graph 2)
DTMF
DTMF tones may be transmitted and received at the 4-wire port.
subscribers set decodes the FSK signal and displays the calling party's number.
Loop Length
The MH88625 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.
DID Operation
For DID operation, the Tip and Ring reversal is controlled by the REVC pin. A logic level one causes Tip and Ring to be reversed. This can be controlled by a Mitel Codec (MT896X) system drive output (refer to Figure 9b).
OPS Operation
As shown in the application diagram, Figure 9a, the ringing voltage, typically 90Vrms 20Hz biased at V Bat, is applied to the subscriber line through an external relay K1. Enabling of the relay is performed by applying a logic low level to the relay driver control input, RGNDC. Figure 9c, shows how balanced ringing can be accommodated if required.
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.
Central Office Operation
The MH88625 can be configured for ground start C.O. applications with the addition of Q1, D1 and K2, as shown in Figure 9c. 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 toll call has been dialled. The Tip/Ring reversal can indicate a toll diversion signal.
On-Hook Transmission
The MH88625 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
2-194
Preliminary Information
-VBat
MH88625
SYSTEM GROUND
+5V LGND VDD VBat VEE GRX0 GRX1 -5V AGND LCA TX GTXO TF1 TF2 SHK UD Z1 TIP Z600 RNGC REVC VRLY RING RRD K1 RF1 RF2 K1 +5V VX RX VR
CODEC
MH88625
GTX1
LINE CONTROLLER LOGIC
~
-VBat
90VRMS 20Hz
NS
RGND
Figure 9a - 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)
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MH88625
-VBat
Preliminary Information
SYSTEM GROUND
+5V LGND VDD VBat VEE RX GRX0 GRX1 -5V AGND LCA TX GTX0 TF1 TF2 SHK UD Z1 TIP Z600 RNGC REVC VRLY RING RRD RF1 RF2 NS RGND VR VX
LOGIC LOGIC LOGIC
MH88625
GTX1
LINE CONTROLLER LOGIC
+5V
Figure 9b - DID SLIC Configuration Applications Circuit
2-196
Preliminary Information
MH88625
-VBat
SYSTEM GROUND
+5V VDD VEE
LGND
VBat
RX GRX0
VR VX
CODEC
MH88625
-5V AGND
GRX1 LCA TX GTX0
TF2 GTX1 K1A TF1 SHK UD K2 Z1 +5V TIP Z600 RNGC REVC VRLY RING RRD K1B RF1 RGND ESE ES1 45VRMS 20Hz K1 +5V Q1 D1 K2
LINE CONTROLLER LOGIC
~~
-V Bat
RF2
12/16kHz METERING SOURCE
45VRMS 20Hz NS
Figure 9c - LS/GS C.O. SLIC Applications Circuit - Balanced Ringing
2-197
MH88625
Preliminary Information
T
F1 R1
T
MH88625
PRO1 LINE
R
F2 R2 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 9d - Suggested Protection Circuit
Side View
0.080 Max (2.0 Max)
4.20 + 0.020 (50.8 + 0.5)
0.58+0.02 (14.7+0.5)
40
21
0.010 + 0.002 (0.25 + 0.05) 0.12 Max (3.1 Max) * Notes: 1) Not to scale 2) Dimensions in inches). 3) (Dimensions in millimetres). *Dimensions to centre of pin & tolerance non accumulative. 0.05 + 0.01 (1.3 + 0.5) * 0.05 + 0.02 (1.3 + 0.05) 0.020 + 0.05 (0.51 + 0.13) * * 0.18 + 0.02 (4.6 + 0.5)
0.100 + 0.10 (2.54 + 0.13)
Figure 10 - Mechanical Data
2-198


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