product summary CX74059: rx asic for cdma, pcs, and amps applications applications ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? tri-mode cdma handsets features battery cell operation (2.7 v < vcc < 3.3 v) two-step gain control pcs lna three-step gain control cellular lna external pot resistor to adjust lna bias current independent cellular and pcs mixers single lo input signal for cellular and pcs mixer frequency divide-by-2 to switch mixer lo from pcs to cell frequency range buffered lo signal for tx upconverter single external uhf vco is only required 90 db dynamic range variable gain amplifier i/q demodulator 200 to 600 mhz vhf oscillator vco on/off control for standby current optimization 6 mm x 6 mm rflga? package with downset paddle description the CX74059 application-specific integrated circuit (asic) is a single intermediate frequency (if), multi-mode, dual-band receiver designed for use in code division multiple access (cdma) portable phones implementing both cellular and personal communications system (pcs), as well as advanced mobile phone system (amps) modes. this highly integrated, super-heterodyne receiver comprises all the critical components to implement the receiver chain: starting from the low-noise amplifier (lna) to the in-phase and quadrature (i/q) demodulator stage, excluding the external surface acoustic wave (saw) filters, bypass, and external matching components. two lnas are in the front-end of the receiver. the cellular lna has three gain stages (bypass, mid, and high), and the pcs lna has two gain stages (bypass and high). after rf signal amplification and saw filtering from the antenna, the signal is mixed down from rf to the if by the mixer C one independent mixer for each individual band. the cdma cellular and pcs mixer outputs are shared in a differential output to accommodate a single if frequency plan, while the amps mixer differential output is matched to a differential input saw filter, and saw filter output is matched single-ended into a variable gain amplifier (vga). after external if filtering, the signal is amplified by a vga and fed to an i/q demodulator, which outputs baseband i/q signals. the vga has a minimum dynamic range of 90 db with a control voltage range from 0.3 to 2.5 v, and it is common to all modes. a vhf oscillator with external tank circuitry provides the local oscillator (lo) frequency for the i/q demodulator. with different frequency bands input to the mixer, the mixer lo is tuned to have the same if frequency output. since if frequency is the same for all bands, it usually refers to a single if frequency plan at 183.6 mhz. one lo port for the amps, cdma, and pcs mixer is designed on the device. a divide-by-2 is used to switch the mixer lo frequency from pcs to the cellular band. in addition, the lo oscillator signal is coupled out and further amplified, providing an rf signal for the transmitter upconverter lo port (lo_out). the noise figure, gain, and third order input intercept point (iip3) of each stage in the receiver are optimized to meet the system requirements for amps and cdma modes per tia/eia- 98-c. the CX74059 uses bicmos technology and is designed for low cost, high performance, and a high level of integration. a block diagram of the CX74059 is shown in figure 1. skyw orks so lut i ons , inc . pro p r i et ary an d c o nf ide n t i a l 1 103086a [781] 376-3000 i fax [781] 376-3100 i sales@ skyw o rksinc. c om i www.skywor ksinc.c om february 5, 2003
product summary i CX74059 rf_bias_res amps_vga_in lo_out pcs/cell_lo vcc_mix pcs_mix_byp cdma_mix_in pcs_mix_in pcs_lna_out cell_lna_bias_res cell_lna_out pcs_lna_bias_res mix_out+ mix_out? amps_mix_out+ amps_mix_out? vcc_if lna_ctrl_1 pcs_lna_in cell_lna_in lna_ctrl_0 cell_lna_gnd vcc_vco vcc_rf_bias 31 30 29 28 27 26 25 24 23 22 21 1 2 3 4 5 6 7 8 9 10 11 vga_in+ vga_in- buff_en vgactrl q ? q+ i? i+ vco_on vcotnk+ vcotnk? 90 o 32 33 34 35 36 37 38 39 40 pll? pll+ 20 19 18 17 16 15 14 13 12 2 sleep fm cell/pcs c1386 figure 2. CX74059 rx asic block diagram ordering information model name manufacturing part number product revision receiver asic CX74059-12 ? 2002, 2003 skyworks solutions, inc. all rights reserved. information in this document is pr ovided in connection with skyworks solutions, inc. ("skyworks") products. these materials are provided by skyworks as a service to its customers and may be used for informational purpo ses only. skyworks assumes no responsibility for errors or omis sions in these materials. skyworks may make changes to its products, specifications and product de scriptions at any time, without notice. skyworks makes n o c o mmitmen t to update the information and shall have no responsibility whatsoever for conflicts, incompatibilities, or other difficulties aris in g from fu tu re c h an g e s to its pr oduct s and pr oduct descr i pt ions. no license, express or implied, by estoppel or otherwise, to any int e llect ual pr oper t y r i ght s is gr ant e d by t h is document . exce pt as may be pr ovided in skyworks? terms and conditions of sale for such pr oducts, skyworks assumes no liability whatsoever. th es e ma teria ls a r e prov ided "a s is " with out wa rra nty of a n y k i nd, eith er expres s or implied, rela ting to s a l e a nd/or us e of skyworks? products including warrant ies relating to fitness for a particular purp os e, merch a n ta bility , pe rformance, quality or non-infringement of any patent, copyright or other intellectual property right. skywo rks further does not warrant the accuracy or completenes s of th e informa t ion, text, g r a p h i cs or oth e r i tems conta i ned with in th es e ma teria ls . s k y work s s h a ll not be lia b l e for any special, indirect, incidental, or c onsequential damages, includin g with out limita tion, los t rev e nues or los t profits th at ma y res u lt from th e us e of th es e ma teria ls . s k ywor ks? pr oduct s ar e not int e nded f o r use in medical, lif esav ing or life-sustaining applicatio ns. skyworks? customers using o r selling skyworks? pr oduct s f o r use in such applicat ions do so at t h eir own r isk and agree to fully indemnify skyworks for any damages resulting f rom such improper use or sale. the following are trademarks of skyworks solutions, inc.: skywor ks?, the skyworks symbol, spr?, single package radio?, and ?bre akt hr ough simplicity??. product names or services list ed in this publication are fo r identification purposes only, and may be trademarks of t h ir d par t ies. thir d -par t y br ands and names ar e t h e pr oper t y of their respective owners. rflga? is a trademark of conexant systems, inc. additional information, posted at www.skywor ksinc.com, is incorporated by reference. general information skyworks solutions, inc. 20 sylvan rd. woburn, ma 01801 www.skyworksinc.com
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