LTC1540 - Nanopower Comparator with Reference


  • Ultralow Quiescent Current: 0.3µA Typ
  • Reference Output Drives 0.01µF Capacitor
  • Adjustable Hysteresis
  • Available in 3mm x 3mm x 0.8mm DFN Package
  • Wide Supply Range: 2V to 11V
  • Input Voltage Range Includes the Negative Supply
  • Reference Output Sources Up to 1mA
  • TTL/CMOS Compatible Outputs
  • 60µs Propagation Delay with 10mV Overdrive
  • No Crowbar Current
  • 40mA Continuous Source Current
  • Pin Compatible with LTC1440, MAX921, MAX931

Typical Application

LTC1540 Typical Application
LTC1540 Typical Application


The LTC1540 is an ultralow power, single comparator with built-in reference. The comparator’s features include less than 0.6µA supply current over the commercial temperature range, a 1.182V ±2% reference, programmable hysteresis and TTL/CMOS outputs that sink and source current. The reference output can drive a bypass capacitor of up to 0.01µF without oscillation.

The comparator operates from a single 2V to 11V supply or a dual ±1V to ±5.5V supply. Comparator hysteresis is easily programmed by using two resistors and the HYST pin. Each comparator’s input operates from the negative supply to within 1.3V of the positive supply. The comparator output stage can continuously source up to 40mA. By eliminating the cross-conducting current that normally occur when the comparator changes logic states, power supply glitches are eliminated.

The LTC1540 is available in the 8-pin MSOP and SO packages. For space limited applications, the LTC1540 is available in a 3mm x 3mm low profile (0.8mm) dual finepitch leadless package (DFN).


For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LTC1540CDD#PBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC1540CDD#TRPBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC1540CMS8#PBF MS-8 MS8 C 05-08-1660 Yes
LTC1540CMS8#TRPBF MS-8 MS8 C 05-08-1660 Yes
LTC1540CS8#PBF SO-8 S8 C 05-08-1610 (S8) Yes
LTC1540CS8#TRPBF SO-8 S8 C 05-08-1610 (S8) Yes
LTC1540IDD#PBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC1540IDD#TRPBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC1540IMS8#PBF MS-8 MS8 I 05-08-1660 Yes
LTC1540IMS8#TRPBF MS-8 MS8 I 05-08-1660 Yes
LTC1540IS8#PBF SO-8 S8 I 05-08-1610 (S8) Yes
LTC1540IS8#TRPBF SO-8 S8 I 05-08-1610 (S8) Yes

LTC1540 Package Drawing
LTC1540 Package Drawing
LTC1540 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LTC1540CDD#PBF 3x3 DFN-8 C $2.59 $1.90 Yes
LTC1540CDD#TRPBF 3x3 DFN-8 C $1.95 Yes
LTC1540CMS8#PBF MS-8 C $2.15 $1.80 Yes
LTC1540CMS8#TRPBF MS-8 C $1.86 Yes
LTC1540CS8#PBF SO-8 C $1.90 $1.60 Yes
LTC1540CS8#TRPBF SO-8 C $1.66 Yes
LTC1540IDD#PBF 3x3 DFN-8 I $3.32 $2.44 Yes
LTC1540IDD#TRPBF 3x3 DFN-8 I $2.49 Yes
LTC1540IMS8#PBF MS-8 I $3.14 $2.34 Yes
LTC1540IMS8#TRPBF MS-8 I $2.39 Yes
LTC1540IS8#PBF SO-8 I $2.25 $1.85 Yes
LTC1540IS8#TRPBF SO-8 I $1.91 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC600A LTC1540CDD | Nano-power Voltage Comparator with Built In Voltage Reference in DFN Package $50.00
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