Philips HEF4751VU, HEF4751VDB, HEF4751VD, HEC4751VDB Datasheet

DATA SH EET

Product specification
File under Integrated Circuits, IC04

January 1995

INTEGRATED CIRCUITS

HEF4751V
LSI

Universal divider

For a complete data sheet, please also download:

•The IC04 LOCMOS HE4000B Logic
Family Specifications HEF, HEC

•The IC04 LOCMOS HE4000B Logic
Package Outlines/Information HEF, HEC

January 1995 2

Philips Semiconductors Product specification

Universal divider

HEF4751V

LSI

DESCRIPTION

The HEF4751V is a universal divider (U.D.) intended for
use in high performance phase lock loop frequency
synthesizer systems. It consists of a chain of counters
operating in a programmable feedback mode.
Programmable feedback signals are generated for up to
three external (fast) ÷ 10/11 prescaler.

The system comprising one HEF4751V U.D. together with
prescalers is a fully programmable divider with a maximum
configuration of: 5 decimal stages, a programmable mode
M stage (1 ≤ M ≤ 16, non-decimal fraction channel
selection), and a mode H stage (H = 1 or 2, stage for half
channel offset).
Programming is performed in BCD code in a bit-parallel,
digit-serial format.

To accommodate fixed or variable frequency offset, two
numbers are applied in parallel, one being subtracted from
the other to produce the internal programme.
The decade selection address is generated by an internal
programme counter which may run continuously or on
demand. Two or more universal dividers can be cascaded,
each extra U.D. (in slave mode) adds two decades to the
system. The combination retains the full programmability
and features of a single U.D. The U.D. provides a fast
output signal FF at output OFF, which can have a phase
jitter of ± 1 system input period, to allow fast frequency
locking. The slow output signal FS at output OFS, which is
jitter-free, is used for fine phase control at a lower speed.

Fig.1 Pinning diagram.

SUPPLY VOLTAGE

FAMILY DATA, IDDLIMITS category LSI

See Family Specifications

HEF4751VP(N): 28-lead DIL; plastic (SOT117)
HEF4751VD(F): 28-lead DIL; ceramic (cerdip) (SOT135V)
HEF4751VT(D): 28-lead SO; plastic (SOT136A)
( ): Package Designator North America

RATING RECOMMENDED OPERATING

−0,5 to + 18 4,5 to 12,5 V

January 1995 3

Philips Semiconductors Product specification

Universal divider

HEF4751V

LSI

Fig.2 Block diagram.