MAX3580
Direct-Conversion TV Tuner
4 _______________________________________________________________________________________
AC ELECTRICAL CHARACTERISTICS (continued)
(MAX3580 EV kit, V
CC
= +3.1V to +3.5V, V
GND
= 0V. V
RF_AGC
= V
BB_AGC
= +2.85V, RF input terminated into a 75Ω load, BBI_ and
BBQ_ loaded by R
L
greater than 2kΩ and C
L
less than 10pF, VCO active, registers are set according to the recommended default
register conditions, unless otherwise noted. Typical values are at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SIGMA-DELTA FRACTIONAL-N SYNTHESIZER
REFERENCE OSCILLATOR
Frequency f
REF
4 27 MHz
Input Impedance Z
IN
10 kΩ
Voltage Gain 30 V/V
Output Impedance Z
OUT
15 Ω
Buffered Output 10kΩ || 10pF load 0.7 V
P-P
DIVIDERS
RF N Divider Ratio (Notes 12, 13) 12 251 —
RF R Divider Ratio VHF band operation requires R divider = 2 1 2 —
Fractional-N Resolution 20 Bits
LO PHASE DETECTOR AND CHARGE PUMP
Phase-Detector Frequency 4 27 MHz
Gain = 0 600
Charge-Pump Current I
CP
Gain = 1 1200
µA
Charge-Pump Tri-State Current -10 +10 µA
Charge-Pump Compliance
Range
Charge-pump positive to negative current
matching of ≤ ±5%
0.4
V
CC
-
0.4
V
LOCAL OSCILLATOR
Tuning Frequency Range f
OSC
Tank Frequency 2160 4400 MHz
VCO Dividers 4 16 —
BASEBAND STAGE
Nominal Output Voltage (Note 2) 1 V
P-P
1dB Output Compression Point P
1dB
Differential voltage at 3MHz 1.6 2 V
P-P
Output Impedance Differential 60 Ω
Passband AGC Range V
BB_AGC
= 0.5V to 2.85V 30 50 dB
Passband Cutoff Attenuation
At 3.8MHz (UHF Mode);
at 3.325MHz (VHF Mode)
2 5 dB
Passband Differential Gain Error
2MHz to 3.8MHz, I channel vs. Q channel
(UHF mode)
-0.45 +0.45 dB
Passband Group Delay
From DC to 3.8MHz over any 1.1kHz band
(UHF mode)
5 ns
Group Delay Mismatch
From 0.1MHz to 3.8MHz, I channel vs. Q
channel (UHF mode) (Note 9)
< 2 ns
