RF212
Image-Reject Front End for Dual or Tri-Band GSM Applications
The RF212 device is available as a dual-band (EGSM900/DCS1800) front end or
as a tri-band (EGSM900/DCS1800/PCS1900) front end for Global System for
Features
Mobile Communications (GSM) mobile telephony applications. Each device
integrates all the required front-end components after the frequency pre-select
filters. These components include the Low Noise Amplifiers (LNAs), the internal
image-reject filters, mixers, and a Local Oscillator (LO) amplifier.
• Supports EGSM
• LNA and mixer for RF to IF conversion
• 12 dB or 20 dB switchable gain step
• Minimum 35 dB of image rejection
• No external post-LNA filters required
• Common Intermediate Frequency (IF) port for all
bands
• IF range from 350 MHz to 450 MHz
• High isolation LO input buffer
• Differential IF output
The main advantage of the RF212 is its ability to provide a minimum of 35 dB of
image rejection for each band. The block diagrams of the devices are shown in
Figures 1 and 2. The device packages and pin configurations are shown in Figures
3 and 4.
• High dynamic range with low current consumption
• Three-cell battery operation (2.7 to 3.6 V)
• 20-pin Exposed paddle, Thin Shrink Small Outline
Package (ETSSOP)
Applications
• Dual/tri-band digital cellular mobile telephony
(EGSM900/DCS1800, or
EGSM900/DCS1800/PCS1900)
LOIN
LOIN
LNA900IN
IFout
LNA900IN
LNA1800IN
LNA1900IN
IFout
LNA1800IN
Band Select 1
Band Select 1
control
control
Band Select 2
Step
Sel
Gain
Sel
Step
Sel
Gain
Sel
C0002
C0001
Figure 1. RF212 Dual-Band Device Block Diagram
Figure 2. RF212 Tri-Band Device Block Diagram
Data Sheet
Conexant
Doc. No. 100780D
May 24, 2000
Proprietary Information and Specifications are Subject to Change