GE865 Hardware User Guide
1vv0300799 Rev.17– 2017-05-11
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 52 of 75
WARNING.
When in
Single Ended
configuration, the unused output line must be left open: if
this constraint is not respected, the output stage will be damaged.
“EAR_MT” Output Lines
line coupling single-ended
differential
AC
DC
output load resistance
≥ 14 Ω
internal output resistance
4 Ω (
typical
)
signal bandwidth
150 ÷4000 Hz
@
-3dB
max. differential output voltage
1.31 V
rms
(
typical, open circuit
)
differential output voltage 328mV
rms
/16 Ω
@ -12dBFS
(*)
volume increment
2 dB per step
volume steps
10
(*)
0dBFS
is the
normalized
overall Analog Gain equal to
3,7V
pp
differential
11.
General Purpose I/O
The general purpose I/O pads can be configured to act in three different ways:
•
input
•
output
TIP
: We suggest driving the load differentially , thus the output swing will double and the need
for the big output coupling capacitor avoided. However if particular OEM application needs,
also a Single Ended
(S.E)
circuitry can be implemented but the output power will be reduced
four times.
The OEM circuitry shall be designed to reduce the common mode noise typically generated on
the ground plane,getting the maximum power output from the device (low resistance tracks).
