and

4) Select R2. In this example, we will choose 1k

Ω.

6) Solve for R1.

where R1

Board Layout and Bypassing

Power-supply bypass capacitors are not typically need-

ed, but would be called for in cases where supply

impedance is high, supply leads are long, or excessive

noise is expected on the supply lines. Use 100nF

bypass capacitors under these conditions. Minimize

signal trace lengths to reduce stray capacitance.

Reference Output/Load Capacitance

The MAX904_/MAX905_ do not require an output

capacitor on REF for frequency stability. They are sta-

ble for capacitive loads up to 4.7nF. However, in appli-

cations where the load or the supply can experience

step changes, an output capacitor will reduce the

amount of overshoot (or undershoot) and assist the cir-

cuit’s transient response. When an application is not

subject to transient conditions, the REF capacitor can

be omitted.

Biasing for Data Recovery

Digital data is often embedded into a bandwidth- and

amplitude-limited analog path. Recovering the data can

be difficult. Figure 2 compares the input signal to a

time-averaged version of itself. This self- biases the

threshold to the average input voltage for optimal noise

margin.

Even severe phase distortion is eliminated from the dig-

ital output signal. Be sure to choose R1 and C1 so that

digital data stream.

Chip Information

MAX9040/41/50/51 TRANSISTOR COUNT: 204

MAX9042/43/52/53 TRANSISTOR COUNT: 280

f

1

2R1C1

π

0 050

5

1000

1 1000

.

=

+













R

VV

R

RR

HYS

CC

=

+













2

12

V

R

RR

+













25 1

2

12

.

V

R

RR

+













25

25

2

12

..

Micropower, Single-Supply,

SOT23 Comparator + Precision Reference ICs

10

______________________________________________________________________________________

MAX9040–9043

MAX9050–9053

OUT

IN+

IN-

10k

0.1µF

Figure 2. Time Averaging of the Input Signal for Data Recovery