SA541 Datasheet, PDF (4/16 Pages) Sames – PULSE/DTMF SWITCHABLE DIALLERS

SA541
Keypad
R1 R2 R3 R4 C1 C2 C3
Nominal frequency (Hz)
697 770 852 941 1209 1336 1477
Deviation from nominal (%)
-,22
-,07 -,10 +,19 -,15 -,17 -,20
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.
The devices feature automatic storage of a single telephone number of up to 32 digits
for Last Number Redial (LNR) purposes. The low current consumption of the SA54X1
ensures memory retention while powered from the line.
Two modes of operation are available. The first is a LD/DTMF mode which operates
normally in LD mode, but can be switched temporarily via the keypad to DTMF mode
during a call. This mode is intended for applications such as home banking, credit-card
verification and other applications requiring low speed data communications. The
second mode allows DTMF dialling only.
The Lock function will be described in the Functional Description.
The SA54X1 is pin compatible with SAMES' SA54X5 family of diallers.
Ordering Information
SA54X1X
Lock Option L:
with (22 pin package)
Blank: without (20 pin package)
On-Hook Current Option
3
5µA @ 2.5V
6
1µA @ 2.5V
9
1µA @ 3V
4
1µA @ 3V (and TBR Period = 300 mSec)
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