Rainbow Electronics MAXQ7667 - Manual (Page 3)

MAXQ7667
16-Bit, RISC, Microcontroller-Based,
Ultrasonic Distance-Measuring System
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ELECTRICAL CHARACTERISTICS (continued)
(V DVDDIO = +5V, V AVDD = +3.3V; V DVDD = +2.5V, system clock (f SYSCLK ) = 16MHz, burst frequency (f BURST ) = bandpass frequency
(f BPF ) = 50kHz, C REFBG = C REF = 1µF in parallel with 0.01µF, f ADCCLK = 2MHz (SAR data rate = 125ksps), T A = T MIN to T MAX , unless
otherwise specified. Typical values are at T A = +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
BANDPASS FILTER
Center Frequency f BPF 25 100 kHz
Passband Width -3dB 0.14 x f BPF kHz
Minimum Stopband
Rejection One decade away from center
frequency
-60 dB
Output Data Rate 10 x f BPF ksps
Output Data Resolution 16 Bits
LOWPASS FILTER
Corner Frequency f LPF -3dB 0.1 x f BPF kHz
Rolloff 40 dB/Decade
Output Data Rate 5 x f BPF ksps
Output Data Resolution 16 Bits
SAR ADC
Measurement 12
Resolution
No missing codes 11
Bits
Integral Nonlinearity Tested at 125ksps ±1 ±2 LSB
Differential Nonlinearity Tested at 125ksps -2 +2 LSB
Offset Error ±1 ±3 mV
Offset-Error Drift ±5 µV/°C
Gain Error ±1 %
Gain-Error Temperature
Coefficient
±0.4 ppmFS/°C
Input-Referred Noise At ADC inputs 400 µV RMS
Unipolar 0 V REF
Differential Input Range
Bipolar -V REF /2 +V REF /2
V
Absolute Input Range 0 V AVDD V
Input Leakage Current ±0.1 µA
Conversion Time 13 ADCCLK cycles at 2MHz 6.5 µs
Input Capacitance 14 pF
Track-and-Hold Acquisition
Time
Three ADCCLK cycles at 2MHz 1.5 µs
Turn-On Time Eight ADCCLK cycles at 2MHz 4 µs
Conversion Clock f ADCCLK 0.5 4 MHz
Conversion Rate
f ADCCLK = 4MHz (not production
tested)
250 ksps