Datasheet

Electrical characteristics ST7538Q
12/44
C
CL
Input capacitance on CL
pin
80 pF
CCL
TH
Current control loop
reference threshold on C
L
pin
Figure 14 1.80 1.90 2.00 V
CCL
HYST
Hysteresis on Current loop
reference threshold
Figure 14 210 250 290 mV
T
RxTx
Carrier Activation Time
Figure 17 - 600 Baud
Xtal=16MHz
0.01 1.6 ms
Figure 17- 1200 Baud
Xtal=16MHz
0.01 800 µs
Figure 17- 2400 Baud
Xtal=16MHz
0.01 400 µs
Figure 17- 4800 Baud
Xtal=16MHz
0.01 200 µs
TAL C
Carrier Stabilization Time
From STEP 16 to zero or
From step 16 to step 31,
Figure 17
Xtal =16MHz
3.2 ms
T
ST
Tstep
Figure 17
Xtal =16MHz
200 µs
Receiver
V
IN
Input Sensitivity (Normal
Mode)
0.5 2
mV
rms
Input Sensitivity (High
Sens.)
250
µV
rms
V
IN
Maximum Input Signal 2
V
rms
R
IN
Input Impedance 80 100 140 kΩ
V
CD
Carrier detection sensitivity
(Normal Mode)
0.5 2
mV
rms
Carrier detection sensitivity
(High Sensitivity Mode)
250
µV
rms
Carrier detection sensitivity
(TxD line forced to “1”)
UART/SPI pin
forced to “1”
V
BU
dB/
µVrms
V
BU
Band in Use Detection
Level
77 85
dB/
µVrms
Table 4. Electrical characteristics (continued)
(AVdd = DVdd = +5V, PAVcc =+9 V, PAVss, SGND = DVss = 0V, -40°C ≤ T
A
≤ 85°C, T
J
< 125 °C, fc = 86kHz,
other control register parameters as default value, unless otherwise specified)
Symbol Parameter Test condition Min Typ Max Unit