7 Application and Implementation

Note

Information in the following applications sections is not part of the TI component specification,

and TI does not warrant its accuracy or completeness. TI’s customers are responsible for

determining suitability of components for their purposes, as well as validating and testing their design

implementation to confirm system functionality.

7.1 Application Information

7.1.1 Adjustable Hysteresis

As a result of a comparator’s high open loop gain, there is a small band of input differential voltage where the

output can toggle back and forth between “logic high” and “logic low” states ("Chatter"). This can cause design

challenges for inputs with slow rise and fall times or systems with excessive noise. These challenges can be

overcome by adding hysteresis to the comparator.

The TLV3603-EP has a LE/HYS pin that can be used to increase the internal hysteresis of the comparator. To

change the internal hysteresis of the comparator, connect a single resistor as shown in the adjusting hysteresis

figure between the LE/HYS pin and VEE. A curve of hysteresis versus resistance is provided below to provide

guidance in setting the desired amount of hysteresis.

OUT

+

VEE

VCC

LE/HYS

IN+

IN

-

Figure 7-1. Adjustable Hysteresis using External

Resistor

OUT

+

VEE

VCC

LE/HYS

IN+

IN

-

DAC

Figure 7-2. Adjustable Hysteresis using External

Voltage

RHYST (k)

0

200

400

600

800

1000

0

10

20

30

40

50

60

70

80

-55°C

-40°C

25°C

85°C

125°C

Figure 7-3. Hysteresis vs. RHYS at VCC = 5V

LE/HYST Voltage to VEE (V)

0.5

0.7

0.9

1.1

1.3

1.5

1.7

1.9

2.1

2.3

0

10

20

30

40

50

60

70

-55°C

-40°C

25°C

85°C

125°C

Figure 7-4. Hysteresis vs. VHYS at VCC = 5V

To provide dynamic hysteresis, an external 0.7V to 1.2V voltage, such as from a DAC, can be forced into the

LE/HYST pin, as shown in Figure 7-2 and Figure 7-4. The LE/HYST pin can be internally modeled as a 40k

resistor in series with a 1.25V source to VEE, so any driving circuitry must be able to sink up to 32uA. Note that

the output goes into latch when LE/HYST is ≤ 400mV, or go into shutdown when ≥ 1.25V.

TLV3603-EP

SNOSDK3 – SEPTEMBER 2024

www.ti.com

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