LTC3569 - Triple Buck Regulator with 1.2A and Two 600mA Outputs and Individual Programmable References
Features
- Three Independent Current Mode Buck DC/DC Regulators (1.2A and 2 × 600mA)
- Single Pin Programmable VFB Servo Voltages from 800mV Down to 425mV (in 25mV Steps)
- Pull VFB High to Make Each 600mA Buck a Slave for Higher Current Operation
- Pulse-Skipping or Burst Mode® Operation
- Programmable Switching Frequency (1MHz to 3MHz) or Fixed 2.25MHz
- Synchronizable (1.2MHz to 3MHz)
- VIN Range 2.5V to 5.5V
- All Regulators Internally Compensated
- PGOOD Output Flag
- Quiescent Current <100μA (All Regulators in Burst Mode Operation)
- Zero Shutdown Current
- Overtemperature and Short-Circuit Protection
- Tiny 3mm × 3mm, 3mm × 4mm 20-Lead QFN and Thermally Enhanced TSSOP FE-16 Packages
AEC-Q100 data available for specific packages
Typical Application
Description
The LTC®3569 contains three monolithic, synchronous step-down DC/DC converters. Intended for medium power applications, it operates over a 2.5V to 5.5V input voltage range. The operating frequency is adjustable from 1MHz to 3MHz, allowing the use of tiny, low cost capacitors and inductors. The three output voltages are independently programmable by toggling the EN pins up to 15 times, lowering the 800mV FB references by 25mV per cycle. The first buck regulator sources load currents up to 1200mA. The other two buck regulators each provide 600mA.
The two 600mA buck regulators can also be configured to operate as slave power stages, running in parallel with another internal buck regulator to supply higher load currents. When operating as parallel, slave output stages, discrete external components are shared and available output currents sum together.
Packaging
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 Drawing |
RoHS |
|---|---|---|---|---|---|
| LTC3569EFE#PBF | TSSOP-16 | FE | E | 05-08-1663 (BA) | Yes |
| LTC3569EFE#TRPBF | TSSOP-16 | FE | E | 05-08-1663 (BA) | Yes |
| LTC3569EUD#PBF | 3x3 QFN-20 | UD | E | 05-08-1720 | Yes |
| LTC3569EUD#TRPBF | 3x3 QFN-20 | UD | E | 05-08-1720 | Yes |
| LTC3569EUDC#PBF | 3x4 QFN-20 | UDC | E | 05-08-1742 | Yes |
| LTC3569EUDC#TRPBF | 3x4 QFN-20 | UDC | E | 05-08-1742 | Yes |
| LTC3569IFE#PBF | TSSOP-16 | FE | I | 05-08-1663 (BA) | Yes |
| LTC3569IFE#TRPBF | TSSOP-16 | FE | I | 05-08-1663 (BA) | Yes |
| LTC3569IUD#PBF | 3x3 QFN-20 | UD | I | 05-08-1720 | Yes |
| LTC3569IUD#TRPBF | 3x3 QFN-20 | UD | I | 05-08-1720 | Yes |
| LTC3569IUDC#PBF | 3x4 QFN-20 | UDC | I | 05-08-1742 | Yes |
| LTC3569IUDC#TRPBF | 3x4 QFN-20 | UDC | I | 05-08-1742 | Yes |
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 (1-99) |
Price (1k)* |
RoHS | |
|---|---|---|---|---|---|---|
| LTC3569EFE#PBF | TSSOP-16 | E | $4.57 | $3.20 | Yes | |
| LTC3569EFE#TRPBF | TSSOP-16 | E | $3.26 | Yes | ||
| LTC3569EUD#PBF | 3x3 QFN-20 | E | $4.43 | $3.10 | Yes | |
| LTC3569EUD#TRPBF | 3x3 QFN-20 | E | $3.16 | Yes | ||
| LTC3569EUDC#PBF | 3x4 QFN-20 | E | $4.43 | $3.10 | Yes | |
| LTC3569EUDC#TRPBF | 3x4 QFN-20 | E | $3.16 | Yes | ||
| LTC3569IFE#PBF | TSSOP-16 | I | $5.36 | $3.75 | Yes | |
| LTC3569IFE#TRPBF | TSSOP-16 | I | $3.81 | Yes | ||
| LTC3569IUD#PBF | 3x3 QFN-20 | I | $5.22 | $3.65 | Yes | |
| LTC3569IUD#TRPBF | 3x3 QFN-20 | I | $3.71 | Yes | ||
| LTC3569IUDC#PBF | 3x4 QFN-20 | I | $5.22 | $3.65 | Yes | |
| LTC3569IUDC#TRPBF | 3x4 QFN-20 | I | $3.71 | Yes | ||
| Buy Now • Request Samples | ||||||
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 |
|---|---|---|---|
| DC1340A | LTC3569EUD Demo Board | Triple Buck Regulator with 1.2A and Two 600mA Outputs and Individual Programmable References | $150.00 | |
| Buy Now | |||
Designed for Automotive and Transportation Applications
AEC-Q100 data is available for these specific part numbers. Please contact your local sales representative for more information regarding reliability reports or to inquire about parts that are not included. For more information, view our Automotive and Transportation page
| Part Number | Package | Temp | Price (1-99) |
Price (1k)* |
RoHS | |
|---|---|---|---|---|---|---|
| LTC3569IFE#PBF | TSSOP-16 | I | $5.36 | $3.75 | Yes | |
| LTC3569IFE#TRPBF | TSSOP-16 | I | $3.81 | Yes | ||
| LTC3569IUD#PBF | 3x3 QFN-20 | I | $5.22 | $3.65 | Yes | |
| LTC3569IUD#TRPBF | 3x3 QFN-20 | I | $3.71 | Yes | ||
| LTC3569IUDC#PBF | 3x4 QFN-20 | I | $5.22 | $3.65 | Yes | |
| LTC3569IUDC#TRPBF | 3x4 QFN-20 | I | $3.71 | Yes | ||
| Buy Now • Request Samples | ||||||
Applications
- Portable Applications with Multiple Supply Rails
- General Purpose Step-Down DC/DC
- Dynamic Voltage Scaling Applications
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Design Tools
LTspice
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LTC3569
Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.
