1995 Jul 07

2

Philips Semiconductors

Product specification

Low-voltage frequency synthesizer

for radio telephones

UMA1019AM

FEATURES

• Low current from 3 V supply

• Fully programmable RF divider

• 3-line serial interface bus

• Independent fully programmable reference divider,

driven from external crystal oscillator

• Dual phase detector outputs to allow fast frequency

switching

• Dual power-down modes.

APPLICATIONS

• 1 to 1.7 GHz mobile telephones

• Portable battery-powered radio equipment.

GENERAL DESCRIPTION

The UMA1019AM BICMOS device integrates prescalers,

a programmable divider, and phase comparator to

implement a phase-locked loop.

The device is designed to operate from 3 NiCd cells, in

pocket phones, with low current and nominal 5 V supplies.

The synthesizer operates at RF input frequencies up to

1.7 GHz. The 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

The phase detector uses two charge pumps, one provides

normal loop feedback, while the other is only active during

fast mode to speed-up switching. All charge pump currents

(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

supply voltage

2.7

−

5.5

V

supply current

−

9.4

−

mA

current in power-down mode per supply

−

12

−µA

RF input frequency

1000

1500

1700

MHz

crystal reference input frequency

3

−

40

MHz

phase comparator frequency

−

200

−

kHz

operating ambient temperature

−30

−

+85

°C

TYPE NUMBER

PACKAGE

NAME

DESCRIPTION

VERSION

UMA1019AM

SSOP20

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

SOT266-1