Datasheet

ST7540 Electrical characteristics
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V
SENSE
V
SENSE
Input
impedance
36 kΩ
CL
TH
Current control loop
reference threshold on
CL pin
Figure 17 1.80 1.90 2.00 V
CL
HYST
Hysteresis on current
loop reference
threshold
Figure 17 210 250 290 mV
T
RxTx
Carrier activation time
Figure 21 - 600
Baud Xtal = 16MHz
1.6 ms
Figure 21- 1200 Baud
Xtal = 16MHz
800 µs
Figure 21- 2400 Baud
Xtal = 16MHz
400 µs
Figure 21- 4800 Baud
Xtal = 16MHz
200 µs
T
ALC
Carrier stabilization
time
from STEP 16 to zero
or from step 16 to step
31,
Figure 21
Xtal = 16MHz
3.2 ms
T
ST
Tstep
Figure 21
Xtal = 16MHz
200 µs
Power amplifier
PA
IN(Offset)
Input terminals
OFFSET
±18 mV
GBWP
Gain bandwidth
product
100 MHz
R
IN
Input resistance at
PA_IN+ and PA_IN-
pins
PA_IN+ vs. Vss
(1)
1 MΩ
PA_IN- vs. Vss
(1)
1 MΩ
C
IN
Input capacitance at
PA_IN+ and PA_IN-
pins
PA_IN+ vs. Vss
(1)
5pF
PA_IN- vs. Vss
(1)
5pF
CMRR
Common mode
rejection ratio
40 dB
Table 5. Electrical characteristics (continued)
( V
DD
= +5V, V
CC
=+9 V, V
SS
= S V
SS
= GND = 0V,-40°C ≤ T
A
≤ 85°C, T
J
< 125°C,
unless otherwise specified)
Symbol Parameter Test condition Min. Typ. Max. Unit