MT8889 Zarlink Semiconductor, Inc., MT8889 Datasheet - Page 11

• Manufacturer Part Number: MT8889
• Description: Integrated DTMF Transceiver with Adaptive Micro Interface
• Manufacturer: Zarlink Semiconductor, Inc.

BIT
b0
b1
b2
b3
Notes:
R1, R2 = 100 kΩ 1%
R3 = 374 kΩ 1%
R4 = 3.3 kΩ 10%
R5 = 4.7 MΩ 10%
R
C1 = 100 nF 5%
C2 = 100 nF 5%
C3 = 100 nF 10%*
C4 = 10 nF 10%
X-tal = 3.579545 MHz
DTMF/CP
INPUT
DTMF
OUTPUT
L
= 10 k Ω (min.)
TRANSMIT DATA
REGISTER EMPTY
(BURST MODE ONLY)
RECEIVE DATA REGISTER
FULL
DELAYED STEERING
C1
NAME
IRQ
R1
C4
Figure 13 - Application Circuit (Single-Ended Input)
R5
R
X-tal
R2
L
Table 8
Interrupt has occurred. Bit one
(b1) or bit two (b2) is set.
and transmitter is ready for new
data.
Valid data is in the Receive Data
Register.
Set upon the valid detection of the
absence of a DTMF signal.
Pause duration has terminated
* Microprocessor based systems can inject undesirable noise into the supply rails.
The performance of the MT8889C can be optimized by keeping
noise on the supply rails to a minimum. The decoupling capacitor (C3) should be
connected close to the device and ground loops should be avoided.
.
STATUS FLAG SET
Status Register Description
IN+
IN-
GS
VRef
VSS
OSC1
OSC2
TONE
R/W/WR
CS
MT8880C
IRQ/CP
DS/RD
St/GT
VDD
RS0
ESt
D3
D2
D1
D0
R3
Interrupt is inactive. Cleared after
Status Register is read.
Cleared after Status Register is
read or when in non-burst mode.
Cleared after Status Register is
read.
Cleared upon the detection of a
valid DTMF signal.
STATUS FLAG CLEARED
C2
V
DD
R4
C3
MT8889C
To µP
or µC
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