SA541 Sames, SA541 Datasheet
SA541
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SA541 Summary of contents
Page 1
... 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 SA5413 - 5µA @ 2.5V SA5416 - 1µA @ 2.5V SA5419 - 1µA @ 3.0V Call, barring/locking feature available on the SA54L1 PIN CONNECTIONS: SA54L1 PDS039-SA541-001 SA541, SA54L1 1/16 REV. B ...
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... SA541 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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... Total harmonic Distortion: 0-4KHz sames Min Typ 1,8 2,4 0 <0.2 <0.2 <0.2 1,5 2,2 0, 500 600 50,000 Min Typ 560 1,5 2 1,5 0-10KHz 2,5 0-50KHz 5,0 0-200KHz 6,5 SA541 Max Unit Notes 5,7 V For memory retention 5 µ 2. µ 2. µ 3.0V DD µ OUT is low 1,0 mA 200 µ -1mA 0,3 ...
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... SA541 Keypad Nominal frequency (Hz) Deviation from nominal (%) -,22 There will be an additional error due to a deviation in the oscillator frequency from 560 kHz. FUNCTIONAL OVERVIEW The SAMES SA54X1 is a family of keypad switchable Loop Disconnect (LD)/Dual Tone multi-Frequency (DTMF) dialler devices for use in low-cost, dual dialling mode telephone instruments ...
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... Block Diagram Figure 1 depicts the SA54X1 block diagram, while Table 1 lists the respective pin functions. Figure 1: SA54X1 Block Diagram sames SA541 5/16 ...
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... SA541 SA541 SA54L1 Designation OSC OUT 5 5 OSC MUTE 3 3 MASK and 6 6 FILT FILT OUT OUT 1 1 IMP 2 2 SELECT ...
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... A key is accepted as valid when two successive scanning pulses from the same COLUMN are seen on a ROW input. Hence, the minimum bounce-free key closure period which is necessary to guarantee detection is 14ms(plus the oscillator start up time if it was not already running). sames SA541 7/16 ...
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... SA541 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 SA54X1 family. ...
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... ELR is supported via the C3 pin. If this pin is connected to ground for a minimum of 20ms during an ELR operation, the chip will offer the same operating protocol as for TBR. The ELR function may be achieved by use of the circuit shown in Figure use of a double contact switch. sames SA541 9/16 ...
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... SA541 Figure 2: Earth Loop Recall Application 7. 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. 8. 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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... If keys are activated faster than this, they are placed in a temporary store and then sent to line at the maximum rate. 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. sames SA541 at the start of the DD 11/16 ...
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... SA541 DTMF Mode Timing Diagram 10. 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 ...
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... Figure 5: LD Mode Timing Diagram t = Pre-digit Pause (= Break Period (60ms or 67ms Make Period (40ms or 33ms Post-digit Make (= Inter-digit Pause (800ms or 500ms) 5 Figure 6: Detailed Timing for IMP Output sames SA541 13/16 ...
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... SA541 11. LOCKING FACILITY This feature is available on the SA54L1. Pin 11 (LOCK) should be connected the device locked and to V can be controlled by an inexpensive low voltage SPDT switch. When locked, columns 1,2 and 3 on the keypad are disabled making it impossible to dial out any digits ...
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... Figure 7: Typical Application Circuit: Powered via Reference Diode Figure 8: Typical Application Circuit: Powered via Speech Circuit sames SA541 15/16 ...
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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; ...