GC5316 datasheet(7/75 Pages) TI

7 / 75 page

GC5316

SLWS154A − JANUARY 2004 − REVISED MARCH 2004

www.ti.com

2.2

DDC Organization

CD M A D D C A

DD C 0

CD M A D D C B

4to 1

Sw itch

4to 1

Swi tch

From Input

I nte rface

DD C 1

DD C 2

DD C 3

DD C 4

DD C 5

DD C 6

DD C 7

DD C 8

DD C 9

DD C 10

DD C 11

Figure 5. Receive DDC Blocks

The GC5316 provides downconversion for up to 24 CDMA2000 receive channels or 12 UMTS receive channels.

Downconversion channels are organized into 12 DDC blocks. Each DDC block provides two CDMA2000 DDC

channels, A and B, or one UMTS channel. Each DDC block has its own register set and may be programmed

independently (except for parameters specifying the configuration of the rx_distribution bus).

Two DDC blocks (for example, DDC 0 and DDC 1) can be strapped together to form a single UMTS DDC channel

with double-length filtering. The GC5316 can therefore provide six UMTS DDC channels with double-length FIR

filtering.

Configuration parameters ending in _a apply to the A CDMA channel or to the UMTS channel. Parameters ending

in _b apply the B CDMA channel and are unused in UMTS mode. Many parameters are shared between the A and

B channels in CDMA mode (such as filter coefficients), while key parameters are independent for the two channels

(such as frequency, phase, and gain).

Both CDMA DDC channels in a block can be independently tuned, though they would likely be used as diversity pairs

and tuned to the same frequency. Filter coefficients are shared between the two CDMA DDC channels within a block.

Table 5. Programming

VARIABLE

DESCRIPTION

ddc_duc_ena

When set turns on the DDC. When cleared the clock to the DDC is

stopped reducing its power consumption to essentially zero.

cdma_mode

When set, puts the DDC block in dual CDMA2000 mode.

GC5316 Datasheet(PDF) 7 Page - Texas Instruments

GC5316 Datasheet(HTML) 7 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

Datasheet Download

Link URL