User guide

MAX3540
Complete Single-Conversion Television Tuner
4 _______________________________________________________________________________________
AC ELECTRICAL CHARACTERISTICS (continued)
(MAX3540 Evaluation Kit, V
CC
= +3.1V to +3.5V, 75Ω system impedance, default register settings, V
RFAGC
= V
IFAGC
= +3V (minimum
attenuation), T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.)
PARAMETER CONDITIONS MIN TYP MAX UNITS
IF VARIABLE-GAIN AMPLIFIER
Input Impedance Balanced 2000 Ω
Output Impedance Balanced (Note 1) 300 Ω
Maximum gain setting,
V
IFAGC
= 3V
54 56 65
Passband Voltage Gain
S our ce l oad = 300Ω ,
outp ut l oad = 300Ω
Minimum gain setting,
V
IFAGC
= 0.5V
21
dB
Passband Gain Flatness 40MHz to 48MHz (Note 1) 1.2 dB
Output Voltage V
IFAGC
= 3V (Note 1) 2 V
P-P
AGC Gain Slope V
IFAGC
= 3V to 0.5V (Note 1) 30 dB/V
Equivalent Input Voltage
Noise Density
At 44MHz, maximum gain, V
IFAGC
= 3V (Note 1) 7.3 nV/√Hz
Noise Figure Change vs.
Attenuation
< 0.35 dB/dB
IM3 V
OUT
= 1.5V
P-P
, 40dB < gain < 60dB (Note 1) -54 dBc
IF OVERLOAD DETECTOR (see the IF Overload Detector section)
Output Overload Attack Point 0.7 V
P-P
Attack-Point Accuracy ±1 dB
Detector Output Voltage Range
Negative polarity, overload reduces V
DET
(open collector, 0.3mA sink)
0.5 3.0 V
Detector Gain 70 V/V
FREQUENCY SYNTHESIZER
REFERENCE OSCILLATOR
Frequency 4 MHz
DIVIDERS
RF N-Divider Ratio 256 32,767
RF R-Divider Ratio 8 127
LO PHASE DETECTOR AND CHARGE PUMP
Comparison Frequency 31.50 250.00 kHz
CP = 00 0.5
CP = 01 1
CP = 10 1.5
Charge-Pump Current
CP = 11 2
mA
C har g e- P um p Thr ee- S tate C ur r ent ±5 nA
Charge-Pump Current Matching 5%
LOCAL OSCILLATOR (OSCILLATOR WITH NARROW BAND LOOP)
VCO Tuning Range Tank frequency 2160 4400 MHz
VCO Tuning Gain Tank oscillator gain 500 MHz/V
2-WIRE SERIAL INTERFACE
Clock Frequency 400 kHz
Note 1: Guaranteed by design and characterization.