Datasheet

MAX1472
300MHz-to-450MHz Low-Power,
Crystal-Based ASK Transmitter
3
ELECTRICAL CHARACTERISTICS (continued)
( Typical Application Circuit , output power is referenced to 50Ω, V
DD
= 2.1V to 3.6V, V
ENABLE
= V
DD
, T
A
= -40°C to +125°C, unless
otherwise noted. Typical values are at V
DD
= 2.7V, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
PHASE-LOCKED LOOP PERFORMANCE
VCO Gain 330 MHz/V
f
OFFSET
=100kHz -84
f
RF
= 315MHz
f
OFFSET
= 1MHz -91
f
OFFSET
=100kHz -82
Phase Noise
f
RF
= 433MHz
f
OFFSET
= 1MHz -89
dBc/Hz
f
RF
= 315MHz -50
Maximum Carrier Harmonics
f
RF
= 433MHz -50
dBc
f
RF
= 315MHz -75
Reference Spur
f
RF
= 433MHz -81
dBc
Loop Bandwidth 1.6 MHz
Crystal Frequency f
XTAL
f
RF
/ 32 MHz
Oscillator Input Capacitance From each XTAL pin to GND 6.2 pF
Frequency Pushing by V
DD
3 ppm/V
DIGITAL INPUTS
Data Input High V
IH
V
D D
- 0.25 V
Data Input Low V
IL
0.25 V
Maximum Input Current 2nA
Pulldown Current 25 µA
Note 1: 100% tested at T
A
= +25°C. Guaranteed by design and characterization over temperature.
Note 2: 50% duty cycle at 10kHz data.
Note 3: Guaranteed by design and characterization, not production tested.
Note 4: Generally limited by PC board layout.
Note 5: Output power can be adjusted with external resistor.
Note 6: Guaranteed by design and characterization at f
RF
= 315MHz.
Note 7: V
ENABLE
< V
IL
to V
ENABLE
> V
IH
. f
OFFSET
is defined as the frequency deviation from the desired carrier frequency.
Note 8: V
ENABLE
> V
IH
, V
DATA
> V
IH
, Efficiency = P
OUT
/(V
DD
x I
DD
).
Note 9: V
ENABLE
> V
IH
, DATA toggled from V
IL
to V
IH
, 10kHz, 50% duty cycle, Efficiency = P
OUT
/(V
DD
x I
DD
).