Data Sheet AS2578 /B Austria Mikro Systeme International TELEPHONE CONTROLLER WITH 13 MEMORIES AND 2-WIRE BUS Key Features General Description ❑ ❑ ❑ ❑ ❑ ❑ The AS2578 /B are a versatile repertory LD/MF diallers with a melody generator, a ring frequency discriminator and a 2-wire interface to EEPROM. Together with the AS2520/1, the AS2578 /B form a coherent basis for a fully electronic telephone with a wide range of options. ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ ❑ Low operating voltage Low current consumption, standby ≤ 0.1 µA Oscillator using Xtal or ceramic resonator (3.58 MHz) Serial interface to external EEPROM Consistent, simple and usable procedures The settings are programmed via the keyboard and stored in EEPROM or set by pin options Dialler: Data protection with 20 digit FIFO Sliding cursor protocol with comparison Automatic pause generation Temporary MF select via keyboard 30 digit LNR (Last Number Redial) 13 x 20 digit memory (RAM) on chip Tone Ringer: Ring frequency discrimination 3 tone melody with 4 different repetition rates Volume of melodies can be set in 4 steps The AS2578 /B are especially designed to adapt to different PTT specifications. A RAM is on chip for last number redial, 3 direct dial and 10 numbers with abbreviated dialling. To allow easy use under a PABX, the device incorporates automatic pause insertion and sliding cursor procedure as selectable options (AS2578) or centrex keys (AS2578B). The device can be used with or without EEPROM as appropriate. When an EEPROM is connected, all RAM content is stored in the EEPROM by power loss. The circuit provides the possibility to set different modes of operation (LM codes) via the keyboard or via pin options, e.g. default signalling mode, automatic pause insertion, flash or ground loop and settings of volume and melodies. Package Available in 28 pin DIP and PLCC. Block Diagramme Vss VDD (AS2578B) 1 2 3 MUTE M1 A 4 5 6 SET M2 B 7 8 9 LNR M3 C * 0 # R MEM D HS KEYSCAN HOOK STATE POR CE MODE OSCILLATOR 3.58 MHz CONTROL DP MASK GL AP (AS2578 only) MV RR MF DIAL REDIAL DTMF MELODY MO MUTE SCL SERIAL INTERFACE SDA 13 X 20 1 X 30 RAM FIFO RING FREQUENCY DETECTOR FCI AS2578 /B Rev. 3 1 March 1997 Data Sheet AS2578 /B Pin Description Pin # Symbol Function 1 2 3 4 C4 C3 C2 C1 Keyboard Columns 5 HS Hook Switch Input This input is active high with internal pull-down resistor. 6 MODE Signalling (LD/MF) Default Mode Select Input Mode pin High Open Low Function LD default mode, make/break pulse 33/66 ms MF only LD default mode, make/break pulse 40/60 ms 7 CE Chip Enable Input This input is active high with internal pull-down resistor and is used to initiate setup procedures. 8 9 OSC2 OSC1 Oscillator Input Oscillator Output Oscillator pins for Xtal or ceramic resonator (3.58 MHz). When a ceramic resonator is used a capacitor (10 - 22 pF) must be connected from each of the oscillator pins to VSS. 10 Vss 11 TONE DTMF Tone Output The dual tones provided at this output have a level independent of the supply voltage in the operating range from 2.5 to 5.5V. 13 SDA 14 SCL Serial Data I/O SDA is a bidirectional pin with an open drain with internal pull-up resistor and is used to transfer data into and out of a compatible EEPROM. Serial Clock Line Output The SCL output is an open drain with internal pull-up resistor and is used to clock data into and out of a compatible EEPROM. 15 FCI Frequency Comparator Input Schmitt trigger input for ring frequency discrimination. 12 MO Melody Generator Output Melodies for tone ringing are generated on this output. The output signal is PDM. 16 MUTE Mute Output This push-pull output is high during dialling and when mute key has been activated, otherwise low. 17 MASK Mask Output This push-pull output is high during pulsing (make and break periods). Negative Power Supply Continues… Rev. 3 2 March 1997 Data Sheet AS2578 /B Pin Description cont´d Pin # Symbol 18 DPN 19 GL 20 VDD 21 22 23 24 R4 R3 R2 R1 Keyboard Rows 25 C5 Keyboard Column (AS2578) This column is for the memory keys C6 Keyboard Column (AS2578B) This column is for centrex keys (A - D keys). Automatic pause insertion and Temporary MF select 1 are fixed enabled (AP open) AP Access Pause Select Input (AS2578) This input is used to select the automatic access pause insertion or sliding cursor (no centrex keys): 26 Function Dial Pulse Output This is the push-pull output for controlling the hook-switch transistor. It is low during onhook and break periods and high during off-hook (see timing diagrammes). Ground Loop Output This push-pull output is high during ground loop Positive Power Supply AP pin High Open Low Function Sliding cursor enabled Automatic pause insertion enabled Sliding cursor and pause disabled Temporary MF select 2 Temporary MF select 1 Temporary MF select 1 C5 Keyboard Column (AS2578B) This column is for the memory keys 27 MV Melody Volume Select Input This input is used to select the volume of the melodies in 4 steps by connecting the MV pin to row 1, 2, or 3. Leaving the pin open is the default setting (max. volume). 28 RR Repetition Rate Select Input This input is used to select the repetition rate of the melodies. 4 different rates can be selected by either leaving the pin open (default) or connecting it to column 1, 2, or 3. Note: "Open" means ≥ 100 kΩ. Power On Reset Initial Setup The on chip power on reset circuit monitors the supply voltage (VDD). As long as VDD remains below the internal reference voltage, Vref (typically 1.1V), the oscillator is inhibited. When VDD rises above Vref (tRISE = 1 µs/V to 50 ms/V), a reset signal is generated to assure correct startup. A low to high transition on the CE input will initiate an automatic setup, i.e. the pin options are scanned and (when an EEPROM is connected) the stored LM codes and melody settings are read from the EEPROM. This is done independently of the hook state (see timing diagrammes). Rev. 3 3 March 1997 Data Sheet AS2578 /B Furthermore, the mode can be selected by setting the LM code (see setup menu). If no LM code is set, the mode will be determined by the MODE pin. Valid Keys The keyscanning is enabled when CE or HS are high. During setup the keyboard is disabled. A valid key is detected from the keyboard by connecting the appropriate row to the column. This can be done using an n x m keyboard matrix with single contacts. Positive and negative edges of each contact are debounced. The debounce time is 15 ms. When default LD mode is selected, a temporary change to MF mode can be invoked by pressing * (AP = high, AS2578 only) or Set, * , Set. When the circuit is in temporary MF mode, each of the following procedures revert it to default LD mode: Mute Key The mute key is only enabled when off-hook. Depressing the mute key activates and deactivates (toggle switch) the MUTE output, when internal mute is inactive, i.e. in speech mode. - pressing Set, * , Set , Any key entry overwrites a mute activated by the mute key, and mute will be deactivated. - by next On-hook. - pressing recall key (by further entries of the recall key the signalling mode will toggle between MF and LD, Last Number Redial LNR is a facility that allows resignalling of the last manually dialled number without keying in all the digits again. The LNR is repeatable. Centrex Keys (AS2578B only) The alphameric keys accommodate easy use of centrex services. The A, B, C and D keys are only valid in MF mode and are not storable. Pressing one of these keys will invoke the appropriate MF tones to be transmitted. The centrex keys are not stored in the RAM, but are buffered in the FIFO, and subsequently entered digits are also buffered in the FIFO. The current contents of the RAM are overwritten by new entries. A manually entered number is automatically stored in the LNR RAM. The capacity of the RAM is 30 digits. If a number greater than 30 digits is entered, the LNR facility will be inhibited (until new entries < 31 digits) and further entries will be buffered in FIFO. Pressing the recall key after a sequence including centrex keys will reset the RAM counter, and subsequently entered digits will be stored in the RAM. If MF select (Set, * , Set) has been invoked once, then all susequently digits/data will be buffered in the FIFO. Postdialled digits, i.e. digits manually entered after LNR has been invoked, are not stored in RAM but buffered in FIFO. Memory Keys Recall Function The keys M1 to M3 are direct memory access keys and the MEM key is used for abbreviated dialling. A recall activation will invoke a flash (timed loop break) or a ground loop (GL) depending on the selected LM code, which is stored in the external EEPROM (see setup menu). If no LM code is set, depressing the recall key will invoke both a flash and a GL, however, in LD mode a Flash is never executed. 13 numbers can be stored in on chip RAM. Each number can contain up to 20 digits (including pauses). If an EEPROM is connected to the serial bus, the content of the RAM is written into the EEPROM when CE is turned low indicating a power loss. If recall is the first entry in a digit string, it will be stored in LNR RAM when digit(s) are entered after the recall. During programming multible pauses can be inserted by pressing the LNR key. If the recall key is depressed after a digit string has been entered or dialled out, the recall will not be stored, and subsequently entered digits will be stored in the LNR RAM as the new number. Memory dialling is cascadable. Mode Selection The default mode (LD or MF) can be selected by the MODE pin. Rev. 3 If pressing the recall key is not followed by digit entries, the LNR RAM remains intact. 4 March 1997 Data Sheet AS2578 /B After a recall a pause will automatically be generated. The pause time is 3 sec. protocol. The protocol defines any device that sends data onto the bus as a transmitter, and the receiving device as the receiver. The AS2578 /B are controlling the transfer and hence the master. The EEPROM being controlled is the slave. The ground loop (GL) has two pulse lengths, namely a short of 500 ms and a long of 1250 ms. Short GL: If the recall key is depressed for ≤ 540 ms, the GL pulse is 500 ms. The AS2578 /B will always initiate data transfer, and provide the clock for both transmit and receive operations. Therefore, the protocol is for single master applications only. Long GL: If the recall key is depressed for > 540 ms, the GL pulse is 1250 ms. However, a temporary second master can be used to write into the EEPROM when the AS2578 /B are supplied and in idle state. During redial a ground loop is only executed as a long GL (1250 ms). Clock and Data Conventions Data states on the SDA line can change only during SCL low. SDA state changes during SCL high are reserved for indicating start and stop conditions (see figure 1 and 2). Pause Generation Pause introduces a delay in signalling digit strings to accommodate second and subsequent dial tones. Start Condition All commands are preceded by the start condition, which is a high to low transition of SDA when SCL is high. The slave should continuously monitor the SDA and SCL lines for the start condition and must not respond to any command until this condition has been met. Automatic pauses are generated in the following manner: - always after a recall independent of the AP pin - with automatic pause insertion enabled by pin option or LM code, up to two pauses can be automatically inserted at any location of the original entry in the RAM (except location 1 of the digit string), when the mute output goes inactive (in MF mode for more than 1 sec.) before next entry. Stop Condition All communications are terminated by a stop condition, which is low to high transition of SDA when SCL is high. The stop condition is also used to place the slave in the standby power mode. A pause read from the RAM can be terminated (shortened) prior to time out by a low level on AP pin (AS2578 only) during the pause execution. The pause time is 3 sec. Acknowledge Acknowledge is a software convention used to indicate successful data transfers. The transmitting device, either master or slave, will release the bus after transmitting eight bits. During the ninth clock cycle the receiver will pull the SDA line low to acknowledge that it received the eight bits of data (see figure 3). During execution of a pause, mute is inactive, i.e. the circuit is in speech mode. Sliding Cursor Procedure (AS2578 only) The slave should always respond with an acknowledge after recognition of a start condition and its slave address. If both the device and a write operation have been selected, the slave should respond with an acknowledge after receipt of each subsequent eight bit word. To accommodate redialling (LNR) behind a PABX without using automatic pause generation, a sliding cursor protocol is implemented. The sliding cursor is enabled when AP = high. If new entries match the previous RAM contents, pressing the LNR key will dial out the remaining digits. In the read mode, when the EEPROM has transmitted eight bits of data, it should release the SDA line and monitor the line for an acknowledge. If the AS2578 /B respond with an acknowledge and does not generate a stop condition, the EEPROM should continue to transmit data. If the AS2578 /B do not respond with an acknowledge, the EEPROM should terminate further If there is an error in matching, the LNR will be inhibited until next on-hook, and the RAM will contain the new number. Serial Interface The AS2578 /B support a bidirectional bus oriented Rev. 3 5 March 1997 Data Sheet AS2578 /B data transmission and await the stop condition to return to the standby power mode. Tone Generator The tone generator incorporates the DTMF tones and 3 basic frequencies for the tone ringer. DTMF The DTMF generator provides 8 frequencies, namely: SDA SCL data stable data change Low group Row 1 Row 2 Row 3 Row 4 697 Hz 770 Hz 852 Hz 941 Hz High group Col. 1 Col. 2 Col. 3 Col. 6 1209 Hz 1336 Hz 1477 Hz 1633 Hz Figure 1 Data Validity SDA (AS2578B only) SCL start bit The MF tones are in accordance with CEPT recommendations. stop bit Tone Ringer (Melody) The three basic frequencies of the melodies are: Figure 2 Definition of Start and Stop F1 = 800 Hz, F2 = 1067 Hz, and F3 = 1333 Hz (± 5%). SCL from master 1 8 9 The repetition rate can be set via key procedures or by pin options as follows: Data out from Tx Data out from Rx LM code 1 2 (default) 3 4 acknowledge start Figure 3 Acknowledge Response From Receiver The frequency comparator monitors that the ring signal is in the limits as shown in figure 4. 20 30 40 The sequence of the frequencies is controlled by the sequence register as follows: Tol. Sequence Ring frequency 50 60 F1 F2 F3 F1 F2 F3 … The volume of the melodies (MO output) can be set as follows: 70 (Hz) Figure 4 Detection Window of Ringing Signal LM code When a continious valid ring signal is present for 80 ms, the melody generator is activated and remains active until two or more periods of the ring signal are missing. 1 2 3 4 Rev. 3 1 time (50 ms pause) 4 times 7 times 10 times Repetition rate means that a sequence of 6 frequencies is repeated 1 to 10 times within 1 sec. For LM code 1 a pause of 50 ms is inserted between the frequencies to allow a better recognition of the melodies. Frequency Comparator MUST DETECT Repetition rate 6 Volume Steps - 17.5 dB - 11.5 dB - 5.5 dB (default) 0 dB 6 dB 6 dB 5.5 dB March 1997 Data Sheet AS2578 /B LM Codes and Pin Options LM code Pin option Function 02-2* AP = L Automatic pause insertion: off Sliding cursor: off MF select 1 02-3 AP = Hi-Z Automatic pause insertion: on Sliding cursor: off MF select 1 - AP = H Automatic pause insertion: off Sliding cursor: on MF select 2 033* MODE = L LD mode 40/60 GL 033* MODE = H LD mode 33/66 GL 036 - MF mode GL 037 - MF mode Flash - MODE = Hi-Z MF mode GL + Flash 250 - Resets all user settings to default and clears all RAM contents 258 - Clears all RAM contents 5 - 4* MV = Hi-Z Melody volume: 0 dB 5-3 MV = R3 Melody volume: - 5.5 dB 5-2 MV = R2 Melody volume: - 11.5 dB 5 -1 MV = R1 Melody volume: - 17.5 dB 6-1 RR = Hi-Z Repetition rate: 1 time 6 - 2* RR = C1 Repetition rate: 4 times 6-3 RR = C2 Repetition rate: 7 times 6-4 RR = C3 Repetition rate: 10 times (50 ms pause) Note 1: Programming an LM code overwrites pin options, however, LM code 033 can only be selected when the MODE pin is connected to either high or low for selecting the make/break ratio. Not valid LM codes are ignored. LM codes with a '*' are default settings. Note 2: When the AP pin is pulled low during execution of a pause, the pause will be terminated. Note 3: AP pin option not available on AS2578B. Rev. 3 7 March 1997 Data Sheet AS2578 /B Operating Procedures Procedure Principles The procedures for utilizing the features of the AS2578 /B are optimized out of consideration for the human factor in order to: - meet the user´s expectations - be easy to learn and relearn - not invoke any automatic functions which the user doesn´t expect - protect the user from committing critical errors, e.g. dialling wrong numbers, etc. - be consistent, simple and usable - meet the German 1 TR 2 and ETR 2 specifications. Symbols States: Entries: Processing: Idle (on-hook, no ringing) Going off-hook Ringing Going on-hook Speech mode KEY sec Time out (x sec.) or Dialling (LD or MF) Storing (writing into RAM or EEPROM) Pressing a key Entering a number Privacy mute Entry according to text TEXT Programming False programme entry X Enter password 1590 TEXT Processing according to text Melodies activated (ringing) = reading from memory Invalid entry TEXT Rev. 3 State according to text 8 March 1997 Data Sheet AS2578 /B Setup Procedures SET AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 1 AAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA * AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AA A AA ANY OTHER ENTRY 5 or 6 M1-3 Storing Direct Numbers Temporary MF Select Programming Melody FALSE 1590 MEM LNR Storing Indirect Numbers LM Codes: 022 = no AP, no SC 023 = AP, no SC Clear Procedures ANY OTHER ENTRY 033 = LD (MODE pin = VDD or Vss), GL 036 = MF, GL 037 = MF, FL LNR 250 = Resets all settings to default, inhibits LNR and memories 258 = Inhibits LNR and memories ANY OTHER SEQUENCE LNR LM Codes 022 or 023 or 033 or 036 or 037 LM Code 250 LNR SET 022, 023 executed. 033, 036, 037 buffered 022, 023 executed. 033, 036, 037 buffered LNR LM Code 258 SET LNR SET Resets all settings to default Exit programme state SET 40 sec A A Rev. 3 9 March 1997 Data Sheet AS2578 /B Clear Procedures SET ANY OTHER ENTRY 1 5 or 6 * M1-3 Storing Direct Numbers Temporary MF Select Programming Melody ANY OTHER ENTRY LNR MEM Storing Indirect Numbers 1590 Setup Procedures LM Codes: ANY OTHER SEQUENCE LM Code 258 258 = Inhibits LNR and memories LNR SET LNR Exit programme state SET Rev. 3 40 sec 10 March 1997 Data Sheet AS2578 /B Programming Melody SET ANY OTHER ENTRY 5 or 6 1 * Temporary MF Select ANY OTHER ENTRY M1-3 Storing Direct Numbers Setup Procedures & Clear Procedure Key 1, 2, 3, or 4 MEM Storing Indirect Numbers IGNORED LM Codes: SET Executing LM Code (5) 1 = Melody volume - 17.5 dB (5) 2 = Melody volume - 11.1 dB (5) 3 = Melody volume - 5.5 dB (5) 4 = Melody volume 0 dB (default) (6) 1 = Repetition rate 1 (6) 2 = Repetition rate 4 (default) (6) 3 = Repetition rate 7 (6) 4 = Repetition rate 10 Exit programme state SET Rev. 3 40 sec 11 March 1997 Data Sheet AS2578 /B Programming Volume of Melody During Ringing RINGING ANY OTHER ENTRY Key 1, 2, 3, or 4 Only one change during a ringing phase! IGNORED LM Codes: 1 = Volume - 17.5 dB 2 = Volume - 11.5 dB 3 = Volume - 5.5 dB 4 = Volume 0 dB (default) Executing LM Code End of ringing Rev. 3 12 March 1997 Data Sheet AS2578 /B Temporary MF Select 1 (AP pin = open or low) RAM FIFO Set, * , Set Pressing any other key does not change the state. D FIFO R Set, * , Set 2 1 FIFO FIFO R Set, * , Set EXIT FIFO Rev. 3 13 March 1997 Data Sheet AS2578 /B Temporary MF Select 2 (AS2578 only) (AP pin = high) RAM FIFO * Set, * , Set Pressing any other key does not change the state. D FIFO R Set, * , Set 2 1 FIFO R FIFO Set, * , Set * EXIT FIFO Rev. 3 14 March 1997 Data Sheet AS2578 /B Automatic Dialling MEM M1-3 LNR 0 - 9 or Postdialled digits are not stored but buffered in FIFO Rev. 3 15 March 1997 Data Sheet AS2578 /B Storing Numbers SET ANY OTHER ENTRY * 5 or 6 Temporary MF Select 1 Set Procedures Programming Melody M1-3 MEM 0 - 9 M1-3 M1-3 MEM M1-3 SET MEM Exit programme state SET CLEARS SAID RAM MEMORY LOCATION Rev. 3 40 sec CLEARS SAID RAM MEMORY LOCATION 16 March 1997 Data Sheet AS2578 /B Privacy Mute MUTE Rev. 3 17 March 1997 Data Sheet AS2578 /B Electrical Characteristics Absolute Maximum Ratings Positive Supply Voltage ...................................................................................................................-0.3V ≤ VDD ≤ 7V Input Current ................................................................................................................................................± 25 mA Digital Input Voltage ......................................................................................................VSS - 0.3V ≤ VIN ≤ VDD + 0.3V Electrostatic Discharge (HBM) ........................................................................................................................±800V Storage Temperature ......................................................................................................................-65°C to +125°C Recommended Operating Conditions Supply Voltage (except DTMF) .....................................................................................................2.2V ≤ VDD ≤ 5.5V Supply Voltage (DTMF) .................................................................................................................2.5V ≤ VDD ≤ 5.5V Oscillator Frequency ..................................................................................................................................3.58 MHz Operating Temperature ....................................................................................................................- 25°C to +70°C DC Characteristics (Default conditions: recommended operating conditions; outputs unloaded; VDD = 3.5V; AP and MODE = Vss; unless otherwise specified)) Symbol Parameter Conditions IDD0 Standby Current IDD Min Typ Max Units HS = L; CE = L 0.1 µA Standby Current HS = H; Osc. = 0 3.6 µA IDD Operating Current no tones 400 700 µA IDD Operating Current MF/melody 0.9 1.5 mA VIL Input Voltage, Low VSS 0.2 VDD V VIH Line Voltage, High 0.8 VDD VDD V IOL Output Current, Sink VOL = 0.4V IOH Output Current, Source VOH = VDD - 0.4V RHS RCE 1.5 mA 1 mA Pull-down Resistor 1 MΩ Pull-down Resistor 1 MΩ AC Charateristics (Default conditions: recommended operating conditions) Symbol Parameter Conditions Min Typ Max Units tS Clock Startup Time 5 ms tD Key Debounce Time 14.7 ms tHS HS Debounce Time 14.7 ms tSU Setup Time 100 ms Continues… Rev. 3 19 March 1997 Data Sheet AS2578 /B AC Characteristics Cont´d Symbol Parameter Conditions Min Typ Max Units -12.3 -10.8 -9.3 dBm 2.0 2.4 2.8 dB -23 dBr DTMF VMF MF Tone Level High group, RL = 15 kΩ ∆VL-H Preemphasis Low to High RL = 15 kΩ THD Distortion (0.3 - 4 kHz) RL = 15 kΩ, note 3 tTD Tone Duration Note 1 80 82.3 85 ms tITP Inter Tone Pause Note 1 80 82.3 85 ms tTR Tone Rise Time Note 2 5 ms tTF Tone Fall Time Note 2 5 ms LD tDR Dial Rate ±5% tM/B Make/Break Period 10 pps ±5%, MODE = low 40.8/61.2 ms ±5%, MODE = high 33/66 ms tIDP Inter Digit Pause 800 tMO Mute Overhang tFD Flash Duration tGLS Ground Loop, Short R key ≤ 540 ms 495 tGLL Ground Loop, Long R key > 540 ms tAP Automatic Pause 840 880 ms 102 ms 500 505 ms 1200 1250 1300 ms 2.9 3.0 3.1 sec 10 ms tM 100 Melody VMO Melody Output PDM tMD Melody Delay F1 Frequency 1 770 800 830 Hz F2 Frequency 2 1025 1067 1110 Hz F3 Frequency 3 1280 1333 1385 Hz tDT Detection Time 85 ms tTO Detection Time-out fMIN Min. Detection Frequency 19 20 21 Hz fMAX Max. Detection Frequency 58 59 60 Hz 80 note 4 ms Note 1: The values are valid during automatic dialling and are minimum values during manual dialling, i.e. the tones will continue as long as the key is depressed. Note 2: The rise time is the time from 10% of final value till the tone amplitude has reached 90 % of its final value. Note 3: Relative to high group. Note 4: The FCI circuit is reset by POR and on-hook. After a reset the FCI circuit is in a standby state. A positive edge on FCI will start the 73 ms timer and the frequency discrimination is initiated. Whenever a period of the ring frequency is missing, the timer is reset. When a valid ring signal is present for ≥ 73 ms, the melody generator is started and is directly controlled by a valid signal from the FCI circuit. This condition will remain until a new reset. Rev. 3 20 March 1997 Data Sheet AS2578 /B Pin Configurations 28 RR C4 1 28 RR C3 2 27 MV C3 2 27 MV C2 3 26 AP C2 3 26 C5 C1 4 25 C5 C1 4 25 C6 HS 5 24 R1 HS 5 24 R1 MODE 6 23 MODE 6 23 CE 7 22 R2 R3 CE 7 22 R2 R3 OSC2 8 21 R4 OSC2 8 21 R4 OSC1 Vss 9 20 OSC1 Vss 9 20 19 VDD GL 10 19 VDD GL TONE 11 18 DP 12 17 MASK 13 16 MUTE 14 15 FCI 10 TONE 11 18 DP MO 12 17 MASK SDA 13 16 MUTE MO SDA SCL 14 15 FCI SCL AS2578B 1 AS2578 C4 1 C5 MV RR C4 C3 C2 C5 HS MODE R1 MODE R1 CE R2 CE R2 R3 OSC2 R4 OSC1 VDD DP MO GL MASK TONE DP MASK MUTE FCI SCL SDA MO VDD Vss GL TONE MUTE Vss R3 R4 FCI OSC1 C6 AS2578B SCL AS2578 OSC2 1 SDA HS C1 AP MV RR C4 C3 C2 C1 28 Pin DIP 28 Pin PLCC Rev. 3 21 March 1997 Data Sheet AS2578 /B Ordering Information: Part Number AS2578 P AS2578 N AS2578B P AS2578B N Package 28 pin DIP 28 pin PLCC 28 pin DIP 28 pin PLCC Pin 25 C5 C5 C6 C6 Pin 26 AP AP C5 C5 Applications: For application support contact your local AMS sales office. Devices sold by Austria Mikro Systeme are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. Austria Mikro Systeme makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. Austria Mikro Systeme reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with Austria Mikro Systeme for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment are specifically not recommended without additional processing by Austria Mikro Systeme for each application. Copyright 1995-7, Austria Mikro Systeme International AG, Schloss Premstätten, 8141 Unterpremstätten, Austria. Trademarks Registered. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. Rev. 3 22 March 1997