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Ordering Information appears at end of data sheet.
Typical Application Circuit appears at end of data sheet.
Functional Diagram
MAX2870 23.5MHz to 6000MHz Fractional/
Integer-N Synthesizer/VCO
General Description
The MAX2870 is an ultra-wideband phase-locked
loop (PLL) with integrated voltage control oscillators
(VCOs) capable of operating in both integer-N and
fractional-N modes. When combined with an external
reference oscillator and loop filter, the MAX2870 is
a high-performance frequency synthesizer capable
of synthesizing frequencies from 23.5MHz to 6.0GHz
while maintaining superior phase noise and spurious
performance.
The ultra-wide frequency range is achieved with the
help of multiple integrated VCOs covering 3000MHz to
6000MHz, and output dividers ranging from 1 to 128.
The device also provides dual differential output drivers,
which can be independently programmable to deliver
-4dBm to +5dBm output power. Both outputs can be
muted by either software or hardware control.
The MAX2870 is controlled by a 4-wire serial interface and
is compatible with 1.8V control logic. The device is available
in a lead-free, RoHS-compliant, 5mm x 5mm, 32-pin TQFN
package, and operates over an extended -40NC to +85NC
temp
erature range.
Applications
Benets and Features
U Integer and Fractional-N Modes
U Manual or Automatic VCO Selection
U 3000MHz to 6000MHz Fundamental VCO
U Output Binary Buffers/Dividers for Extended
Frequency Range
• 1/2/4/8/16/32/64/128
• 23.5MHz to 6000MHz
U High-Performance PFD
• 105MHz in Integer-N Mode
• 50MHz in Fractional-N Mode
U Reference Frequency Up to 200MHz
U Operates from +3.0V to +3.6V Supply
U Dual Programmable Outputs
• -4dBm to +5dBm
U Analog and Digital Lock Detect Indicators
U Hardware and Software Shutdown Control
U Compatible with 1.8V Control Logic
Wireless Infrastructure
Test and Measurement
Satellite Communications
Wireless LANs/CATV
PMAR/LMAR/Public
Safety Radio
Clock Generation
REF_IN
CLK
DATA
LE
X2
MUXMUX
DIVIDE-BY-2R COUNTER
INTEGER FRAC
MAIN
MODULATOR
MODULUS
VCO
SPI AND
REGISTERS
DIV-BY-
1/2/4/8
MUX
DIV-BY-
1/2/4/8/16
MUX
MUX
LOCK DETECT
CHARGE
PUMP
MUX_OUT
LD
CP_OUT
CP_GND
TUNE
RFOUTA_P
RFOUTB_P
RFOUT_EN
RFOUTA_N
RFOUTB_N
N COUNTER
MAX2870
19-6250; Rev 6; 4/17
