19-2102; Rev 1; 8/03
1.2GHz VCO with Linear
Modulation Input
General Description
Features
The MAX2754 self-contained, linear modulation, volt-
age-controlled oscillator (VCO) is intended for use in
the 2.4GHz to 2.5GHz ISM band, particularly for FSK
modulation systems that utilize a direct frequency-mod-
ulation transmit architecture. This device features a lin-
ear modulation input in addition to the standard
frequency tuning input. The frequency tuning range of
1145MHz to 1250MHz (1/2 LO) also supports an IF up
to 110MHz with low side LO. The VCO is based on
Maxim’s proprietary monolithic VCO technology, where
all VCO components are integrated on-chip, including
the varactor and inductor.
o Fully Monolithic VCO Construction with On-Chip
Inductor and Varactor Tuning Elements
o Guaranteed 1145MHz to 1250MHz Tuning Range
to Support 1/2 LO Applications
o Modulation Linearity Within 4ꢀ
o Precise Modulation Gain (-500kHz/V)
o Low Phase Noise (-137dBc/Hz at 4MHz offset)
o +2.7V to +5.5V Single-Supply Operation
o Low-Current Shutdown Mode
The MAX2754 linear modulation input offers a means to
directly FM modulate the VCO with a constant modula-
tion sensitivity over the tuning voltage input range.
Typical frequency deviation is -500kHz/V which is linear
to 4ꢀ over the guaranteed frequency limits. The tun-
ing input voltage range is +0.4V to +2.4V and the oscil-
lator frequency is factory adjusted to provide
guaranteed limits. The oscillator signal is buffered by
an output amplifier stage (internally matched to 50Ω) to
provide higher output power and isolate the oscillator
from load impedance variations.
o Miniature 8-Pin µMAX Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX2754EUA
-40°C to +85°C
8 µMAX
The MAX2754 operates over a +2.7V to +5.5V supply
range. This device also provides a digitally controlled
shutdown mode to permit implementation of sophisti-
cated power-supply management. In shutdown, the
supply current is reduced to 0.2µA. Even when active,
power consumption is a modest 41mW.
8-pin µMAX
✕
(3mm 5mm)
The MAX2754 is packaged in the miniature 8-pin µMAX
to offer the world’s smallest, complete 2.4GHz direct-
modulation VCO solution.
Typical Operating Circuit
Applications
HomeRF WLAN
V
CC
Bluetooth
V
VREG
CC
REG AND BIAS
2.4GHz Cordless Phones
2.4GHz Wireless Data Radios
330nF
330nF
OUT TO
TUNE
TUNE
OSCILLATOR
CORE
OUT
Pin Configuration
MIXER/
SYNTHESIZER
TOP VIEW
GND1
GND2
SHDN
VREG
TUNE
GND1
MOD
1
2
3
4
8
7
6
5
V
CC
OUT
LINEAR
MODULATION
INTERFACE
MAX2754
MODULATION
MOD
SHDN
GND2
SHDN
VOLTAGE
SIGNAL
MAX2754
µMAX
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.