SA545 Sames, SA545 Datasheet
SA545
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SA545 Summary of contents
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... Low power CMOS technology enables direct operation from Telephone line Keypad switchable Loop-Disconnect to DTMF during a call PIN CONNECTIONS: SA545 sames M63-1961 SA545, SA54L5 Selectable Break:Make Ratios 2:1 or 3:2 Uses inexpensive 560KHz ceramic resonator Earth Loop Recall and Timed Break Recall (Timed Flash) Low on-hook Supply Current Options SA54X53 - 5µ ...
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... SA545 ABSOLUTE MAXIMUM RATINGS * Parameter Supply Voltage Voltage on any pin (except HSW) Voltage on pin HSW Current at any pin (except HSW, FILTOUT and FILTIN) Current at pin FILTOUT Current at pin FILTIN Operating Temperature Storage Temperature * Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device ...
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... If MF OUT is low 1,0 mA 200 µA 2,2 V 0 500 K 600 50,000 I Min Typ Max Unit 560 kHz 68 77 mVrms 97 109 mVrms 1,5 2 2,5 dB 1,5 % 2,5 % 5 SA545 Notes For memory retention -1mA I = +1mA 2,5V<V <5,7V DD 2,5V<V <5,7V DD =100µA,V = Notes No Load No Load at MF OUT 3/18 ...
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... The devices feature automatic storage of a single telephone number digits for Last Number Redial (LNR) purposes as well as10 repertory dialling memories capable of each storing 24 digits. The low current consumption of the SA545 ensures memory retention while powered from the line. ...
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... Block Diagram Figure 1 depicts the SA545 block diagram, while Table 1 lists the respective pin functions of the SA545 and SA54L5. Figure 1: SA54X5 Block Diagram sames SA545 5/18 ...
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... SA545 SA545 SA54L5 Designation OSC OUT 5 5 OSC MUTE 3 3 MASK 6 6 FILT FILT OUT OUT 1 1 IMP 2 2 SELECT HSW ...
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... Hookswitch Operation The HSW input is used to inform the SA545 of whether the telephone is on-hook or off-hook. Logic ‘0’ is recognised as on-hook, Logic ‘1’ is recognised as off-hook. When the HSW input rises from ‘0’ to ‘1’ the off-hook state is recognised immediately and keypad inputs are accepted. However, when the HSW input falls from ‘ ...
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... SA545 Simultaneous Key Depressions: If two keys are pressed simultaneously (i.e. a second key is pressed before the first has been verified), neither key will be accepted until both keys are released and the correct key is pressed again. Table 2 indicates the keypad layout for the SA54X5 family. ...
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... Repertory Dialling (10 Numbers) The SA545 provides 10 repertory stores each of which is 24 digits in length. Any attempt to store a number greater than 24 digits, will cause the store to be automatically cleared. No further digits will be accepted into the store until the whole programming operation is repeated. ...
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... SA545 Notes: i) Only valid keys will be accepted while a store is being programmed (e.g. if REDIAL is pressed while programming a store, it will be ignored). ii) Dual mode (i.e. LD and DTMF) numbers should be programmed into the store using the procedure outlined under 'Dialling Mode Selection'. When redialling from a repertory store LD/DTMF mode change is encountered, dialling will halt (and the speech circuit will be reactivated) until told to continue by the user ...
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... Earth Loop Recall (ELR) / Timed Break Recall (TBR) (Timed Flash) The SA545 supports both TBR and ELR and offers a common operating protocol in both cases. After a Recall (Flash) operation, the dialling mode selected via the SELECT pin will be restored. Only the digits dialled after the ELR/TBR operation will be retained in the LNR store ...
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... SA545 8. Oscillator Circuit This requires an external 560KHz ceramic resonator connected between OSC IN and OSC OUT, providing a timing reference for all chip functions. Consult your resonator supplier for recommendation of a suitable resonator type. 9. Tone Filtering The spectral purity of the DTMF output is sufficient for most applications. However, where lower distortion DTMF tones are required, an on-chip Darlington pair is provided (accessible via pins 6 & ...
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... Dialling from the LNR store occurs at the maximum rate key is held down for longer than 100ms, the tone output will continue until the key is released. DTMF Mode Timing Diagram Figure 4: DTMF Mode Timing Diagram sames SA545 at the start of the DD 13/18 ...
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... SA545 11. Loop Disconnect Dialling (Figures 5 and 6) The MASK output is provided in order to disable the speech circuit during LD dialling. Consequently, the MASK output is normally at logic '1' in the off-hook condition, but changes to logic '0' during LD dialling. MASK also changes to logic '0' in order to signal a Timed Break Recall (Flash) to the line. Both MUTE and MF OUT remain low during LD dialling ...
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... OPTIONS The SA545 has been designed to allow the telephonic manufacturer to cater for different market requirements. The device can be programmed, on request, at the final manufacturing stage enable various attractive options. These options are listed below and are available in any combination ...
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... DTMF tone level of the SA545. In Figure 8, a stabilising voltage from the speech circuit is used to supply the SA545 during DTMF dialling to give accurate tone levels. The SA545 is powered via the 150K resistor during TBR operations and LD dialling breaks, and via T1 during dialling makes. component count, at the expense of allowing a leakage current of about 450µ ...
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... Figure 7: Typical Application Circuit: Powered via Reference Diode Figure 8: Typical Application Circuit: Powered via Speech Circuit sames SA545 17/18 ...
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... The information contained in this document is confidential and proprietary to South African Micro- Electronic Systems (Pty) Ltd ("SAMES) and may not be copied or disclosed to a third party, in whole or in part, without the express written consent of SAMES. The information contained herein is current as of the date of publication; ...