LT1671IS8#PBF

Overview

The LT1671IS8#PBF is a low power, single supply, ground-sensing comparator featuring complementary outputs and an internal latch. It operates from a single 5V or dual ±5V supplies with a total supply voltage range up to 12V. The device offers a propagation delay of 60ns at 20mV overdrive and 85ns at 5mV overdrive. Input offset voltage is typically 0.8mV, with a maximum of 4.0mV across the temperature range. Supply current is 450µA positive and 75µA negative. The input common mode range extends from the negative supply rail to 1.5V below the positive supply.

Feature Summary

• Complementary TTL/CMOS compatible outputs designed for direct logic interfacing
• Internal latch capability retains output data when the LATCH pin is held high
• Input common mode range extends down to the negative supply rail
• Stable operation without minimum input slew rate requirements

Applications

• High speed A/D converters
• Zero-crossing detectors
• Current sense for switching regulators
• Fast pulse height/width discriminators
• Line receivers

Procurement Notes

Verify the specific IS8 suffix indicates industrial temperature grade (-40°C to +85°C) compared to CS8 variants. Confirm RoHS compliance status via official documentation. Ensure ESD protection measures are implemented during handling due to the high-speed nature of the component. Cross-reference pinout compatibility if replacing older LT1394 or LT1016 designs.

Selection Notes

Select this component for applications requiring ground-sensing inputs and low power consumption. The internal latch is suitable for data retention in sampling circuits. Consider the 60ns propagation delay for timing-critical paths. Verify that the input signal amplitude and slew rates align with the specified common mode and offset characteristics for precision performance.

Part Context

This part belongs to the LT1671 family of comparators, which are designed for improved speed and stability. It shares pin compatibility with the LT1394, LT1016, and LT1116, facilitating drop-in replacements in existing designs. The device utilizes a PNP differential input stage, resulting in bias currents flowing out of the inputs.

Replacement Considerations

LT1394IS8#PBF

FAQ

How does the LATCH pin function?

When the LATCH pin is held high, the outputs remain in a latched condition, retaining the input data state independent of subsequent input changes. The pin must be grounded for flow-through operation.

What is the input common mode range?

The input common mode range extends from the negative supply rail (V-) up to 1.5V below the positive supply rail (V+). This allows sensing signals near ground even with a single positive supply.

Can inputs exceed the supply voltages?

Yes, inputs can exceed the positive supply voltage without phase reversal or damage, provided the current does not exceed 10mA through the internal diode. Negative inputs should not fall significantly below the negative rail to avoid substrate diode conduction.