TLV3501-Q1
SBOS533A –SEPTEMBER 2010–REVISED SEPTEMBER 2010
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APPLICATION INFORMATION
The TLV3501-Q1 features high-speed response and includes 6 mV of internal hysteresis for improved noise
immunity with an input common-mode range that extends 0.2 V beyond the power-supply rails.
Shutdown
A shutdown pin allows the device to go into idle when it is not in use. When the shutdown pin is high, the device
draws about 2 mA and the output goes to high impedance. When the shutdown pin is low, the TLV3501-Q1 is
active. When the TLV3501-Q1 shutdown feature is not used, connect the shutdown pin to the most negative
supply, as shown in Figure 15. It takes about 100 ns to come out of shutdown mode.
VS
0.1 mF
2.2 mF
VIN
VOUT
TLV3501-Q1
VREF
Figure 15. Basic Connections for the TLV3501-Q1
Operating Voltage
TLV3501-Q1 comparators are specified for use on a single supply from +2.7 V to +5.5 V (or a dual supply from
±1.35 V to ±2.75 V) over a temperature range of −40°C to +125°C. The device continues to function below this
range, but performance is not specified.
Adding External Hysteresis
The TLV3501-Q1 has a robust performance when used with a good layout. However, comparator inputs have
little noise immunity within the range of specified offset voltage (±5 mV). For slow moving or noisy input signals,
the comparator output may display multiple switching as input signals move through the switching threshold. In
such applications, the 6 mV of internal hysteresis of the TLV3501-Q1 might not be sufficient. In cases where
greater noise immunity is desired, external hysteresis may be added by connecting a small amount of feedback
to the positive. Figure 16 shows a typical topology used to introduce 25 mV of additional hysteresis, for a total of
31-mV hysteresis when operating from a single 5-V supply. Total hysteresis is approximated by Equation 1:
(V+)´R
1
V
=
+ 6mV
HYST
R +R
1
2
(1)
VHYST sets the value of the transition voltage required to switch the comparator output by enlarging the threshold
region, thereby reducing sensitivity to noise.
VS = 5 V
0.1 mF
2.2 mF
VIN
VOUT
TLV3501-Q1
R1 = 51 W
R2 = 10 kW
VREF
Figure 16. Adding Hysteresis to the TLV3501-Q1
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