3. TECHNICAL BRIEF 3. TECHNICAL BRIEF 3.1 General Description The CU720 supports UMT-850, UMTS-1900, GSM-850, GSM-900, DCS-1800, and PCS-1900 based GSM/GPRS/EDGE/UMTS. All receivers and the UMTS transmitter use the radioOne Zero-IF architecture to eliminate intermediate frequencies, directly converting signals between RF and baseband.
3. TECHNICAL BRIEF A generic, high-level functional block diagram of CU720 is shown in Figure 1-1. One antenna collects base station forward link signals and radiates handset reverse link signals. The antenna connects with receive and transmit paths through a FEM(Front End Module)(plus two duplexers for UMTS highband and low-band operations).
RX saw filters(GSM850, GSM900, GSM900, DCS and PCS). The antenna switch module allows multiple operating bands and modes to share the same antenna. In CU720, a common antenna connects to one of six paths: 1) UMTS-850 Rx/Tx, 2) UMTS-1900 Rx/Tx, 3) GSM-850 Rx, 4) GSM-900 Rx, 5) GSM-850/900 Tx(lo band Tx’s share the same path), 6) DCS-1800 Rx, and 7) DCS-1800, PCS-...
• Insertion loss . this component is also in the receive and transmit paths ; In the CU720 typical losses : UMTS850_ Tx = 1.8 dB, Rx = 2.4 dB • Out-of-band rejection or attenuation . the duplexer provides input selectivity for the receiver, output filtering for the transmitter, and isolation between the two.
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3. TECHNICAL BRIEF 3.10.8. LCD Module (IM220DBN2A : LG INNOTEK) - The IM220DBN2A model is a Color TFT Main supplied by LG Innotek. This LCD Module has a 2.2 inch diagonally measured active display area with 240(RGB)X320 resolution. each pixel is divided into Red, Green and Blue sub-pixels and dots which are arranged in vertical stripes.
4. TROUBLE SHOOTING 4.12 USB Troubleshooting USB Initial sequence of CU720 is : USB connected to CU720 power on → USB_VBUS(U401) go to 5V → USB_D+ go to 3.3V → USB_VP and → USB_VN is triggered → USB work. Start...
LGMDP supports Windows 2000/XP where the LG (Ver 4.6 or later) USB modem driver is installed. Additionally, LGMDP allows multi downloading up to 8 handsets at the same time.