E0C63558
Asynchronous System
(Condition: V
DD
=2.2 to 5.5V, V
SS
=0V, Ta=-20 to 70°C)
Characteristic
Min.
Typ.
Max.
Unit
Symbol
∗
1
Start bit detection error time
t
sa
1
0
t
/16
S
Erroneous start bit detection range time
∗
2
t
sa
2
9
t
/16
10
t
/16
S
∗1:
Start bit detection error time is a logical delay time from inputting the start bit until internal sampling begins operating.
(Time as far as AC is excluded.)
∗2:
Erroneous start bit detection range time is a logical range to detect whether a LOW level (start bit) has been input again
after a start bit has been detected and the internal sampling clock has started. When a HIGH level is detected, the start bit detection
circuit is reset and goes into a wait status until the next start bit. (Time as far as AC is excluded.)
Start bit
SIN
Stop bit
t
sa
1
Sampling
clock
t
Erroneous
start bit
detection signal
t
sa
2
q
FSK Demodulator Characteristics
Characteristic
Transfer rate
Bell202 mark (logic 1)
frequency
Bell202 space (logic 0)
frequency
ITU-T V.23 mark (logic 1)
frequency
ITU-T V.23 space (logic 0)
frequency
Signal-to-noise ratio
Band-pass filter gain
∗
1
Symbol
T
RATE
f
B1
f
B0
f
V1
f
V0
SNR
G
BPF
(Unless otherwise specified: V
DD
=5.0V, V
SS
=0V, f
CLK
=3.579545MHz, Ta=-20 to 70°C)
Condition
Min.
Typ.
Max.
Unit
1188
1200
1212
1188
1200
1212
Hz
2178
1280
2068
20
–
–
–
–
–
–
–
–
2200
1300
2100
–
9.2
42.7
42.8
42.7
22.4
3.7
-20.0
-51
2222
1320
2132
–
–
–
–
–
–
–
–
-48
Hz
Hz
Hz
dB
dB
dB
dB
dB
dB
dB
dB
dBm
Carrier detection ON
CD
ON
sensitivity
∗
2
Carrier detection OFF
CD
OFF
V
DD
=5.0V
-57
-54
–
dBm
∗
2
sensitivity
Input clock frequency
f
CLK
-0.1%
3.579545 +0.1% MHz
R
IN
Input AC impedance
V
DD
=5.0V (between TIP/RING pin and V
REF
)
70
100
130
kΩ
t
SUP
FSKON set-up time
20
–
–
mS
t
CDON
Carrier detection response
3
6.25
9
mS
t
CDOFF
time
5
7.5
10
mS
∗1:
Value measured between TIP/RING pin and BPOUT pin
∗2:
The following expressions can be used to calculate the typical values (dBm) of CD
ON
and CD
OFF
when an external resistor R
TR
(10kΩ
Typ.) is connected in series with the TIP pin and the RING pin.
100k
100k
CD
ON
= -51 + 20log(V
DD
×
) [dBm] CD
OFF
= -54 + 20log( V
DD
×
) [dBm]
5
5
R
TR
+ 100k
R
TR
+ 100k
In addition, the following expressions can be used to calculate the sensitivity of CD
ON
and CD
OFF
when an external feedback resistor
is used for the input amplifier (mask option).
G
Amp
= R
5
= R
6
(R
1
= R
2
, R
3
= R
4
, R
5
= R
6
)
R
1
R
2
CD
ON
= -51 + 20log(V
DD
×
R
1
) [dBm]
CD
OFF
= -54 + 20log( V
DD
×
R
1
) [dBm]
5
R
5
5
R
5
300Hz
1200Hz
1700Hz
2200Hz
3000Hz
4000Hz
≥10000Hz
V
DD
=5.0V
8
SEIKO [ SEIKO EPSON CORPORATION ]
