OM5156M datasheet(2/20 Pages) PHILIPS

2 / 20 page

1995 Nov 24

Philips Semiconductors

Product speciﬁcation

Low-voltage dual frequency

synthesizer for radio telephones

OM5156M

FEATURES

• Low current from 3 V supply

• Fully programmable RF divider

• 3-line serial interface bus

• Second synthesizer to control first IF or offset loop

frequency

• Independent fully programmable reference dividers for

each loop, driven from external crystal oscillator

• Dual phase detector outputs to allow fast frequency

switching

• Dual power-down modes.

APPLICATIONS

• 2 GHz mobile telephones

• Portable battery-powered radio equipment.

GENERAL DESCRIPTION

The OM5156M BICMOS device integrates prescalers,

programmable dividers, and phase comparators to

implement two phase-locked loops. The device is

designed to operate from 3 NiCd cells, in pocket phones,

with low current and a wide supply voltage range from

2.7 to 5.5 V.

The principal synthesizer operates at RF input frequencies

up to 2 GHz the auxiliary synthesizer operates at

300 MHz. The auxiliary loop is intended for the first IF or to

transmit offset loop-frequency settings. Each synthesizer

has a fully programmable reference divider. All divider

ratios are supplied via a 3-wire serial programming bus.

Separate power and ground pins are provided to the

analog and digital circuits. The ground leads should be

externally short-circuited to prevent large currents flowing

across the die and thus causing damage. Digital supplies

VDD1 and VDD2 must also be at the same potential. VCC

must be equal to or greater than VDD (i.e. VDD = 3 V and

VCC = 5 V for wider tuning range).

The principal synthesizer phase detector uses two charge

pumps, one provides normal loop feedback, while the

other is only active during fast mode to speed-up

switching. The auxiliary loop has a separate phase

detector. All charge pump currents (gain) are fixed by an

external resistance at pin ISET (pin 14). Only passive loop

filters are used; the charge-pumps function within a wide

voltage compliance range to improve the overall system

performance.

QUICK REFERENCE DATA

ORDERING INFORMATION

SYMBOL

PARAMETER

CONDITIONS

MIN.

TYP.

MAX.

UNIT

VCC, VDD

supply voltage

VCC ≥ VDD

2.7

−

5.5

ICC +IDD

principal synthesizer supply current

auxiliary synthesizer in

power-down mode

−

9.4

−

principal and auxiliary synthesizer

supply current

principal and auxiliary

synthesizers ON

−

12.1

−

ICCPD, IDDPD current in power-down mode per supply

−

−µA

fVCO

principal input frequency

1700

1890

2000

MHz

fAI

auxiliary input frequency

−

300

MHz

fXTAL

crystal reference input frequency

−

MHz

fPPC

principal phase comparator frequency

−

200

−

kHz

fAPC

auxiliary phase comparator frequency

−

200

−

kHz

Tamb

operating ambient temperature

−30

−

+85

°C

TYPE

NUMBER

PACKAGE

NAME

DESCRIPTION

VERSION

OM5156M

SSOP20

plastic shrink small outline package; 20 leads; body width 4.4 mm

SOT266-1

OM5156M Datasheet(PDF) 2 Page - NXP Semiconductors

OM5156M Datasheet(HTML) 2 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Datasheet Download

Link URL