User's Guide

UC864-E-AUTO / AWS-AUTO Hardware User Guide
1vv0300795 Rev.11 – 2010/11/18
Reproduction forbidden without Telit Communications S.p.A’s. written authorization - All Rights Reserved. Page 51 of 78
11.3. OUTPUT LINES (
((
( Speaker)
Speaker)Speaker)
Speaker)
We suggest driving the load differentially from both output drivers, thus the output
swing will double and the need for the output coupling capacitor avoided.
If a particular OEM application needs a Single Ended Output configuration 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 and to get the maximum power output from the
device (low resistance tracks).
(*) WARNING:
(*) WARNING:(*) WARNING:
(*) WARNING:
Using single ended configuration, the unused output line must be left open.
Not respecting this constraint, the output stage will be damaged.
11.3.1. Output Lines Characteristics
Line coupling differential
single-ended
DC
AC
Output load impedance differential 32 ohm (≤ 26)
Differential output impedance ≤ 01 ohm @1.02kHz
Signal bandwidth 150 - 4000 Hz @ -3 dB
Differential output voltage (typ.) 1060 mV
rms
/32 ohm
Max Output Power 70mW @ 32 ohm
Max load capacitance 500pF
“ Ear_MT
Ear_MTEar_MT
Ear_MT ” Output
OutputOutput
Output ( EAR_AMP1 differential amplifier)
Line coupling differen
tial
single-ended
DC
AC
Output load impedance differential
single-
ended
32 ohm (≤ 26)
16 ohm (≤ 12)
S.E. output impedance ≤ 0,5 ohm @ 1.02kHz
signal bandwidth 150 - 4000 Hz @ -3 dB
Differential output voltage (typ.) 833 mV
rms
/32 ohm
Max Output Power @ 32 ohm
@ 16 ohm
44mW differential
22mW single-ended
Max load capacitance 1000pF
“ Ear_HF
Ear_HFEar_HF
Ear_HF ” Output
OutputOutput
Output ( EAR_AMP2 + EAR_AMP3 amplifiers)