SP8853

1.3 GHz Professional Synthesiser

The SP8853 is a low power single chip synthesiser

intended for professional radio applications, containing all the

elements (apart from the loop amplifier) required to build a PLL

frequency synthesis loop

The device is serially programmable by a three-wire data

highway and contains three independent buffers to store one

reference divider word and two local oscillator divider words.

A digital phase detector with two charge pumps,

programmable in phase and gain, are provided to improve

lock-up performance. The preset operation of the charge

pumps can be overwritten or the comparison frequencies

switched to output ports under control of the divider word. The

dual modulus ratio and so operating range is also

programmable through the same word.

A power down mode is incorporated as a battery economy

feature.

The SP8853 is specified at 1.3GHz at -55°C to +125°C (mil

temp) and -40°C to +85°C (ind. temp).

June 2003

FEATURES

‘Dead Band’ Effects

Rapid Frequency Toggling

ABSOLUTE MAXIMUM RATINGS

Supply voltage

Storage temperature

Prescaler input voltage

2

0·3V to 17V

2

55

°C to 1150°C

2·5V p-p

Fig. 1 Pin identification diagram (top view)

ORDERING INFORMATION

SP8853/A/DG, SP8853/A/HC Industrial temperature versions

SP8853/AC/DG, SP8853/AC/HC Military temperature versions

432

1

28

27

26

12

13

14

15

16

17

18

5

6

7

8

9

10

11

25

24

23

22

21

20

19

PD2 OUTPUT

RPD

GROUND

XTAL 1

XTAL2

POWER DOWN

RF INPUT

RF INPUT

SP8853

HC28

detector sense bit in the F1/F2 programming word. The

above diagram is correct when the sense bit is low. See

Table 2 and Fig. 7.

Data Sheet

SP8853

1.3 GHz Professional Synthesiser