
Philips Semiconductors
Product data
SA8028
2.5 GHz sigma delta fractional-N /
760 MHz IF integer frequency synthesizers
2
2002 Feb 22
853-2277 27777
GENERAL DESCRIPTION
The SA8028 BICMOS device integrates programmable dividers,
charge pumps and phase comparators to implement phase–locked
loops. The device is designed to operate from 3 NiCd cells, in
pocket phones, with low current and nominal 3 V supplies.
The synthesizer operates at VCO input frequencies up to 2.5 GHz.
The synthesizer has fully programmable RF, IF, and reference
dividers. All divider ratios are supplied via a 3-wire serial
programming bus. The RF divider is a fractional-N divider with
programmable integer ratios from 33 to 509 and a fractional
resolution of 22 programmable bits (23 bits internal). A 2nd order
sigma-delta modulator is used to achieve fractional division.
Separate power and ground pins are provided to the charge pumps
and digital circuits. VDDCP must be equal to or greater than VDD.
The ground pins should be externally connected to prevent large
currents from flowing across the die and thus causing damage.
The charge pump current (gain) is fully programmable, while ISET is
set by an external resistance at the RSET pin (refer to section 1.5,
RF and IF Charge Pumps). The phase/frequency detector charge
pump outputs allow for implementing a passive loop filter.
FEATURES
Extremely low phase noise:
L(f) = –101 dBc/Hz at 5 kHz offset at 800 MHz
Low power
Programmable Normal & Integral charge pump outputs:
Maximum output = 10.4 mA
Digital fractional spurious compensation
Hardware and software power-down
I
DDsleep < 0.1 A (typ) at VDD = 3.0 V
Seperate supply for V
DD and VDDCP
Programmable loop filter bandwidth
APPLICATIONS
500 to 2500 MHz wireless equipment
Cellular phones, all standards including:
CDMA
: IS95-B,C WCDMA
3G
: WCDMA / UMTS
GSM
: EDGE / GPRS
TDMA
: IS136 and EDGE
GAIT
: GSM and TDMA
WLAN
Wireless PDAs
Satellite tuners and all other high frequency equipment
Extreme fine frequency resolution applications
13
7
2
3
4
5
6
TOP VIEW
1
8
9
10
11
12
14
15
16
17
18
19
20
21
22
23
24
CLOCK
REFin+
REFin–
SR02176
N/C
VDDPre
GND
GNDPre
RFin+
RFin–
GNDCP
PHP
PHI
GND
PHA
IFin
N/C
DA
T
A
STROBE
PON
LOCK
TEST
V
DD
CP
VDDCP
RSET
Figure 1.
HBCC24 pin configuration.
ORDERING INFORMATION
TYPE NUMBER
PACKAGE
NAME
DESCRIPTION
VERSION
SA8028W
HBCC24
Plastic, heatsink bottom chip carrier; 24 terminals; body 4 x 4 x 0.65 mm (CSP package)
SOT564-1