SM6661A Datasheet, PDF (8/14 Pages) Nippon Precision Circuits Inc – Post-amplifier for Gyroscope

SM6661A
Frequency characteristics setting
The frequency characteristics of SM6661A is adjustable by changing the value of external capacitors C₁ and
C₂. The lower cutoff frequency “f_CL” and upper cutoff frequency “f_CH” are determined by the formula below;
(These values should be set to meet the condition “f_CL < f_CH”, in order to construct the band-pass filter.)
1
f_CL = _{(2π × R1 × C1)} [Hz]
1
f_CH = _{(2π × R2 × C2)} [Hz]
External components setting
The values of R₁ and C₁ should be set considering the time constant (τ) that is determined by the formula
below;
τ = R₁ × C₁ [s]
The R₂ resistor value is determined by R₁ resistor value and output gain setting. Note that the offset voltage
increases as the R₂ value increases. The R₂ recommended value is 27kΩ to 330kΩ.
Sleep Mode Function
The SM6661A has the sleep mode function. When SLEEP pin set to “High”, the SM6661A operation becomes
sleep mode. In sleep mode operation, the current consumption becomes up to 1.0µA and VSIG_OUT1 and
VSIG_OUT2 pins are setting high-impedance.
Control pin
SLEEP
LOW
HIGH
SM6661A operation
Normal operation
Sleep mode
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