LTC2645 - Quad 12-/10-/8-Bit PWM to VOUT DACs with 10ppm/°C Reference


  • No Latency PWM-to-Voltage Conversion
  • Voltage Output Updates and Settles within 8μs
  • 100kHz to 30Hz PWM Input Frequency
  • ±2.5LSB Max INL; ±1LSB Max DNL (LTC2645-12)
  • Guaranteed Monotonic
  • Pin-Selectable Internal or External Reference
  • 2.7V to 5.5V Supply Range
  • 1.71V to 5.5V Input Voltage Range
  • Low Power: 4mA at 3V, <1μA Power-Down
  • Guaranteed Operation from –40°C to 125°C
  • 16-Lead MSOP Package

Typical Application

LTC2645 Typical Application
LTC2645 Typical Application


The LTC®2645 is a family of quad 12-, 10-, and 8-bit PWMto- voltage output DACs with an integrated high accuracy, low drift, 10ppm/°C reference in a 16-lead MSOP package. It has rail-to-rail output buffers and is guaranteed monotonic.

The LTC2645 measures the period and pulse width of the PWM input signals and updates the voltage output DACs after each corresponding PWM input rising edge. The DAC outputs update and settle to 12-bit accuracy within 8μs typically and are capable of sourcing and sinking up to 5mA (3V) or 10mA (5V), eliminating voltage ripple and replacing slow analog filters and buffer amplifiers.

The LTC2645 has a full-scale output of 2.5V using the 10ppm/°C internal reference. It can operate with an external reference, which sets the full-scale output equal to the external reference voltage. Each DAC enters a pin-selectable idle state when the PWM input is held unchanged for more than 60ms. The part operates from a single 2.7V to 5.5V supply and supports PWM input voltages from 1.71V to 5.5V.


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

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

Part Number Package Code Temp Package
LTC2645CMS-L10#PBF MS-16 MS C 05-08-1669 Yes
LTC2645CMS-L10#TRPBF MS-16 MS C 05-08-1669 Yes
LTC2645CMS-L12#PBF MS-16 MS C 05-08-1669 Yes
LTC2645CMS-L12#TRPBF MS-16 MS C 05-08-1669 Yes
LTC2645CMS-L8#PBF MS-16 MS C 05-08-1669 Yes
LTC2645CMS-L8#TRPBF MS-16 MS C 05-08-1669 Yes
LTC2645HMS-L10#PBF MS-16 MS H 05-08-1669 Yes
LTC2645HMS-L10#TRPBF MS-16 MS H 05-08-1669 Yes
LTC2645HMS-L12#PBF MS-16 MS H 05-08-1669 Yes
LTC2645HMS-L12#TRPBF MS-16 MS H 05-08-1669 Yes
LTC2645HMS-L8#PBF MS-16 MS H 05-08-1669 Yes
LTC2645HMS-L8#TRPBF MS-16 MS H 05-08-1669 Yes
LTC2645IMS-L10#PBF MS-16 MS I 05-08-1669 Yes
LTC2645IMS-L10#TRPBF MS-16 MS I 05-08-1669 Yes
LTC2645IMS-L12#PBF MS-16 MS I 05-08-1669 Yes
LTC2645IMS-L12#TRPBF MS-16 MS I 05-08-1669 Yes
LTC2645IMS-L8#PBF MS-16 MS I 05-08-1669 Yes
LTC2645IMS-L8#TRPBF MS-16 MS I 05-08-1669 Yes

LTC2645 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
LTC2645CMS-L10#PBF MS-16 C $4.64 $3.25 Yes
LTC2645CMS-L10#TRPBF MS-16 C $4.70 $3.31 Yes
LTC2645CMS-L12#PBF MS-16 C $5.64 $3.95 Yes
LTC2645CMS-L12#TRPBF MS-16 C $5.70 $4.01 Yes
LTC2645CMS-L8#PBF MS-16 C $3.64 $2.55 Yes
LTC2645CMS-L8#TRPBF MS-16 C $3.70 $2.61 Yes
LTC2645HMS-L10#PBF MS-16 H $5.24 $3.67 Yes
LTC2645HMS-L10#TRPBF MS-16 H $5.30 $3.73 Yes
LTC2645HMS-L12#PBF MS-16 H $6.37 $4.46 Yes
LTC2645HMS-L12#TRPBF MS-16 H $6.43 $4.52 Yes
LTC2645HMS-L8#PBF MS-16 H $4.11 $2.88 Yes
LTC2645HMS-L8#TRPBF MS-16 H $4.17 $2.94 Yes
LTC2645IMS-L10#PBF MS-16 I $4.88 $3.41 Yes
LTC2645IMS-L10#TRPBF MS-16 I $4.94 $3.47 Yes
LTC2645IMS-L12#PBF MS-16 I $5.93 $4.15 Yes
LTC2645IMS-L12#TRPBF MS-16 I $5.99 $4.21 Yes
LTC2645IMS-L8#PBF MS-16 I $3.83 $2.68 Yes
LTC2645IMS-L8#TRPBF MS-16 I $3.89 $2.74 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
DC2197A-A LTC2645 Demo Board | QUAD 12-/10-/8-BIT PWM to VOUT DACs (req DC2026) $75.00
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Companion Boards

Part Number Description Price Documentation
DC2026C Linduino One Isolated USB Demo Board: An Arduino- and QuikEval-Compatible Code Development Platform $75.00
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Click here to view our complete list of demo boards


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