LTC1040CN#PBF

Overview

The LTC1040CN#PBF is a dual micropower comparator manufactured using CMOS technology. It features a unique sampled-data architecture that internally switches the comparator ON for short periods to achieve extremely low power consumption, with typical supply current of 1.2mA at maximum sampling frequency and as low as 0.001mA when OFF. The device operates on a single supply from 2.8V to 16V or split supplies ranging from -2.8V to -8V. Key electrical specifications include a guaranteed maximum offset voltage of 0.75mV, a tracking error between input pairs of 0.1%, and an input common mode range extending to both supply rails. The output logic is TTL/CMOS compatible with a 5V supply.

Feature Summary

• Dual differential input structure utilizing sampled data techniques for high accuracy and low power operation
• Micropower consumption achieved through internal switching mechanisms that minimize active time
• Flexible power supply options supporting both single-ended and split-rail configurations
• Integrated pulsed power output capability to drive external resistive networks efficiently

Applications

• Window comparators with symmetric or independent limits
• Bang-bang controllers in thermal management systems
• Battery-powered sensing applications requiring minimal quiescent current
• Remote sensing circuits with fully floating differential inputs

Procurement Notes

Verify the specific package variant required, as the CN designation corresponds to the 18-lead PDIP package. Confirm that the operating temperature range meets the application requirements, as the C-grade specification covers -40°C to +85°C. Ensure that the sampling frequency settings via external RC components align with the desired power consumption levels. Check for any obsolete package status updates from the manufacturer regarding long-term availability.

Selection Notes

Select this component when system power constraints are critical and traditional continuous-power comparators are unsuitable. The LTC1040 is ideal for applications where the input signals can tolerate the sampling nature of the device. Consider the external timing resistor and capacitor values carefully, as they directly influence both the sampling rate and the total system power dissipation. Ensure source impedances are managed properly to maintain accuracy given the finite input resistance characteristics.

Part Context

The LTC1040 belongs to a family of micropower analog comparators designed by Analog Devices (formerly Linear Technology). It distinguishes itself from standard comparators by employing a switched-capacitor input structure rather than a continuous linear amplifier stage. This design choice allows for significant power savings but requires understanding of sampling theory and charge-sharing effects during circuit implementation.

Replacement Considerations

Consult manufacturer documentation for direct pin-compatible alternatives if the 18-lead PDIP package is unavailable. Verify that any substitute maintains the dual differential input topology and micropower switching characteristics. Generic comparators may not offer the same input common mode range or offset voltage guarantees.