Only For Training And Service Purposes - LG GM210 Service Manual

3.3.2.1 Receiver
Low Noise Amplifiers
The LNAs have differential inputs which help minimize the effect of unwanted interferers. The
voltage gain of the LNAs is typically 24 dB. Each LNA can be switch to a low gain mode when
receiving large input signals as part of the AGC system.
Down-Converting Mixers
Two quadrature mixers are used to mix down the signals from the LNAs, one for the high bands (1800
and 1900 MHz) and one for the low bands (850 and 900 MHz). The outputs of the mixers are
connected to the baseband section through an integrated
single pole filter with nominal cut-off frequency of 800kHz.
LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.

Only for training and service purposes

Figure 3-3-2 AD6546 RECEIVER
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3. TECHNICAL BRIEF
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only