MAX7401/MAX7405
8th-Order, Lowpass, Bessel,
Switched-Capacitor Filters
4 _______________________________________________________________________________________
C
OSC
= 1000pF (Note 4)
CONDITIONS
26 34 43f
OSC
Internal Oscillator Frequency
MIN TYP MAX
SYMBOLPARAMETER
Measured at DC
SHDN = GND, CLK driven from 0 to V
DD
Operating mode, no load, IN = OS = COM
V
CLK
= 0 or 3V
0.5V
SDL
SHDN Input Low
V
DD
- 0.5V
SDH
SHDN Input High
60PSRRPower-Supply Rejection Ratio
0.2 1I
SHDN
Shutdown Current
2 3.5
2.7 3.6V
DD
Supply Voltage
0.5V
IL
Clock Input Low
V
DD
- 0.5V
IH
Clock Input High
±15 ±30I
CLK
Clock Input Current
V
V
dB
µA
V
V
V
µA
kHz
UNITS
SHDN Input Leakage Current
V
SHDN
= 0 to V
DD
±0.1 ±10 µA
FILTER CHARACTERISTICS—MAX7401/MAX7405
(V
DD
= +5V for MAX7401, V
DD
= +3V for MAX7405; filter output measured at OUT; 10kΩ || 50pF load to GND at OUT; SHDN = V
DD
;
V
COM =
V
OS =
V
DD
/2;f
CLK
= 100kHz; T
A
= T
MIN
to T
MAX
; unless otherwise noted. Typical values are at T
A
= +25°C.)
Note 1: The maximum f
C
is defined as the clock frequency, f
CLK
= 100 · f
C,
at which the peak SINAD drops to 68dB with a sinu-
soidal input at 0.2f
C
.
Note 2: DC insertion gain is defined as ∆V
OUT
/ ∆V
IN
.
Note 3: OS voltages above V
DD
- 1V saturate the input and result in a 75µA typical input leakage current.
Note 4: For MAX7401, f
OSC
(kHz) ≅ 38 · 10
3
/ C
OSC
(pF). For MAX7405, f
OSC
(kHz) ≅ 34 · 10
3
/ C
OSC
(pF).
CLOCK
POWER REQUIREMENTS
SHUTDOWN
CONDITIONS UNITS
MIN TYP MAX
PARAMETER
mAI
DD
Supply Current
ELECTRICAL CHARACTERISTICS—MAX7405 (continued)
(V
DD
= +3V, filter output measured at OUT, 10kΩ || 50pF load to GND at OUT, OS = COM, 0.1µF from COM to GND,
SHDN = V
DD
, f
CLK
= 100kHz, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
f
IN
= 0.5f
C
-1.0 -0.8 -0.6
f
IN
= f
C
-3.3 -3.0 -2.7
f
IN
= 3f
C
-33 -29
f
IN
= 6f
C
dB
-79 -74
Insertion Gain Relative to
DC Gain
