Samsung SGH-X430 Service Manual page 12

Gsm telephone

Hide thumbs Also See for SGH-X430:

Table of Contents

2 . S G H - X 4 3 0

C i r c u i t

D e s c r i p t i o n

re gis te r are GMSK modulate d according to GSM 2+ s tandards . The re s ulting

phas e information is trans late d into I and Q diffe re ntial output voltage s that can

be conne cte d dire c tly to an RF modulator at the TXOP and TXON pins . The

DSP is notifie d whe n the trans mis s ion is c omple te d. For re ce iving bas e band

data, a DSP can program CSP1093¡¯ s e ve nt timing and control re gis te r with the

e x act time to s tart re ce iving I and Q s ample s through TXIP and TXIN pins .

Whe n that time is re ache d, the control portion of the e ve nt timing and c ontrol

re gis te r will s tart the bas e band re c e ive s e ction conve rting I and Q s ample

pairs . The s ample s are s tore d in a double - buffe re d re gis te r until the re gis te r

contains 32 s ample pairs . CSP1093 the n notifie s the DSP which has ample time

to re ad the information out be fore the ne x t 32 s ample pairs are s tore d. The

voice band ADC conve rte r is s ue s an inte rrupt to the DSP whe ne ve r it finis he s

conve rting a 16- bit PCM word. The DSP the n re ads the ne w input s ample and

s imultane ous ly loads the voice band output DAC c onve rte r with a ne w PCM

output word. The voice band output can be c onne cte d dire ctly to a s pe ake r via

AOUTAN and AOUTAP pins and be conne cte d to a Ear- mic s pe ake r via

AOUTBN and AOUTBP pins .

8) X- TAL(1 3 MHz)

This s ys te m us e s the 13MHz TCXO, TCO- 9141B, Toyocom. AFC control s ignal

form CSP1093 controls fre que ncy from 13MHz x - tal. It ge ne rate s the c lock

fre que nc y. This cloc k is fe d to CSP1093,Tride nt,YMU762 and Silab s olution.

This Document can not be used without Samsung's authorization

SAMSUNG Proprietary-Contents may change without notice

2- 8

Table of Contents