(VCC = 5V, VGND = 0V, MAX9925/MAX9927 gain setting = 1V/V, Mode A1, VBIAS = 2.5V, VPULLUP = 5V, RPULLUP = 1kΩ, CCOUT =

50pF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

INPUT DIFFERENTIAL AMPLIFIER (MAX9924/MAX9926)

Input Voltage Range

IN+, IN-

Guaranteed by CMRR

-0.3

VCC +

0.3

V

Differential Amplifier

Common-Mode Rejection Ratio

CMRR

MAX9924 (Note 5)

60

87

dB

MAX9926 (Note 5)

55

78

Input Resistance

RIN

(Note 5)

65

100

135

kΩ

ADAPTIVE PEAK DETECTION

Zero-Crossing Threshold

VZERO_THRESH

Mode B

operation

(Notes 5, 6)

MAX9924/MAX9925

-6.5

0

+6.5

mV

MAX9926/MAX9927

-6.5

0

+10

Fixed and Adaptive Peak

Threshold

VADAPTIVE

Adaptive peak threshold

33

%PK

VMIN-THRESH

Minimum threshold of hysteresis

comparator MAX9924/MAX9926

(Notes 5, 6)

4

15

30

mV

Minimum threshold of hysteresis

comparator MAX9925/MAX9927

(Notes 5, 6)

20

30

50

VMIN-THRESH - VZERO-THRESH for

MAX9924 (Notes 5, 6)

7

15

26

VMIN-THRESH - VZERO-THRESH for

MAX9926 (Notes 5, 6)

2

15

30

VMIN-THRESH - VZERO-THRESH for

MAX9925/MAX9927 (Notes 5, 6)

19

30

50

Watchdog Timeout for Adaptive

Peak Threshold

tWD

Timing window to reset the adaptive

peak threshold if not triggered (input

level below threshold)

45

85

140

ms

ENTIRE SYSTEM

Comparator Output Low Voltage

VCOUT_OL

0.2

V

Propagation Delay

tPDZ

Overdrive = 2V to 3V, zero-crossing

path

50

ns

tPDA

Overdrive = 2V to 3V, adaptive peak

path

150

COUT Transition Time

tHL-LH

2

ns

Propagation Delay Jitter

tPD-JITTER

Includes noise of differential amplifier

and comparator, f = 10kHz,

VIN = 1VP-P sine wave

20

ns

www.maximintegrated.com

Maxim Integrated │ 3

MAX9924–MAX9927

Variable Reluctance Sensor Interfaces with

Differential Input and Adaptive Peak Threshold

Electrical Characteristics (continued)