Rainbow Electronics MAX7491 - Manual (Page 4)

MAX7490/MAX7491
Dual Universal Switched-Capacitor Filters
4 _______________________________________________________________________________________
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
FILTER
Center Frequency Range f O Mode 1
0.001 to
40
kHz
Clock-to-Center Frequency
Accuracy
f CLK /f O
Mode 1, R1 = R3 = 50k Ω , R2 = 10kΩ,
Q = 5, deviation from 100:1
±0.2 ±0.7 %
Q Accuracy
Mode 1, R1 = R3 = 50k Ω, R2 = 10kΩ,
Q = 5
±0.2 ±2 %
f
O
Temperature Coefficient ±1 ppm/ °C
Q Temperature Coefficient ±5 ppm/ °C
DC Lowpass Gain Accuracy Mode 1, R1 = R2 = 10k Ω ±0.1 ±0.5 %
V OS1 DC offset of input inverter ±3 ±12.5
V OS2 DC offset of 1st integrator ±4 ±15
DC Offset Voltage
(Figure 8)
V OS3 DC offset of 2nd integrator ±4 ±25
mV
Crosstalk (Note 2) f IN = 10kHz -60 dB
Input: COM externally driven
V DD /2
- 0.1
V DD /2
V DD /2
+ 0.1
COM Voltage Range V COM
Output: COM internally driven
V DD /2
- 0.1
V DD /2
V DD /2
+ 0.1
V
Input Resistance at COM R COM 60 80 120 k Ω
Clock Feedthrough Up to 5th harmonic of f
CLK
200 µV
RMS
Noise (Note 3)
Mode 1, R1= R2 = R3 = 10k Ω,
LP output, Q = 1
60 µV
RMS
Output Voltage Swing 0.2 V D D - 0.2 V
Input Leakage Current at COM SHDN = GND, V
COM = 0 to V DD
±0.1 ±10 µA
CLOCK
Maximum Clock Frequency f CLK 4 MHz
EXTCLK = GND, C OSC = 1000pF 95 135 175 kHz Internal Oscillator Frequency
(Note 4)
f OSC
EXTCLK = GND, C OSC = 100pF 1.35 MHz
Clock Input High V DD - 0.5 V
Clock Input Low 0.5 V
Clock Duty Cycle 50 ±5 %
SHDN AND EXTCLK
Input High V IH V DD - 0.5 V
Input Low V IL 0.5 V
Input Leakage Current V INPUT = 0 to V DD
±0.4 ±10 µA
ELECTRICAL CHARACTERISTICS—MAX7491
(V
DD
= EXTCLK = +3V, f
CLK
= 625kHz, T
A
= T
MIN
to T
MAX
, 10k Ω || 50pF load to V
DD
/2 at LP_, BP_, and N_/HP_, SHDN = V
DD
, 0.1µF
from COM to GND, 50% duty-cycle clock input, COM = V DD /2. Typical values are at T A = +25°C, unless otherwise noted.) (Note 1)