LT3752/LT3752-1 - Active Clamp Synchronous Forward Controllers with Internal Housekeeping Controller
Features
- Input Voltage Range: LT3752: 6.5V to 100V, LT3752-1:Limited Only by External Components
- Internal Housekeeping DC/DC Controller
- Programmable Volt-Second Clamp
- High Efficiency Control: Active Clamp, Synchronous Rectification, Programmable Delays
- Short-Circuit (Hiccup Mode) Overcurrent Protection
- Programmable Soft-Start/Stop
- Programmable OVLO and UVLO with Hysteresis
- Programmable Frequency (100kHz to 500kHz)
- Synchronizable to an External Clock
Typical Application
Description
The LT®3752/LT3752-1 are current mode PWM controllers optimized for an active clamp forward converter topology. A DC/DC housekeeping controller is included for improved efficiency and performance. The LT3752 allows operation up to 100V input and the LT3752-1 is optimized for applications with input voltages greater than 100V.
A programmable volt-second clamp allows primary switch duty cycles above 50% for high switch, transformer and rectifier utilization. Active clamp control reduces switch voltage stress and increases efficiency. A synchronous output is available for controlling secondary side synchronous rectification.
The LT3752/LT3752-1 are available in a 38-lead plastic TSSOP package with missing pins for high voltage spacings.
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 |
|---|---|---|---|---|---|
| LT3752EFE-1#PBF | TSSOP-38 | FE | E | 05-08-1865 | Yes |
| LT3752EFE-1#TRPBF | TSSOP-38 | FE | E | 05-08-1865 | Yes |
| LT3752EFE#PBF | TSSOP-38 | FE | E | 05-08-1865 | Yes |
| LT3752EFE#TRPBF | TSSOP-38 | FE | E | 05-08-1865 | Yes |
| LT3752HFE-1#PBF | TSSOP-38 | FE | H | 05-08-1865 | Yes |
| LT3752HFE-1#TRPBF | TSSOP-38 | FE | H | 05-08-1865 | Yes |
| LT3752HFE#PBF | TSSOP-38 | FE | H | 05-08-1865 | Yes |
| LT3752HFE#TRPBF | TSSOP-38 | FE | H | 05-08-1865 | Yes |
| LT3752IFE-1#PBF | TSSOP-38 | FE | I | 05-08-1865 | Yes |
| LT3752IFE-1#TRPBF | TSSOP-38 | FE | I | 05-08-1865 | Yes |
| LT3752IFE#PBF | TSSOP-38 | FE | I | 05-08-1865 | Yes |
| LT3752IFE#TRPBF | TSSOP-38 | FE | I | 05-08-1865 | Yes |
| LT3752MPFE-1#PBF | TSSOP-38 | FE | MP | 05-08-1865 | Yes |
| LT3752MPFE-1#TRPBF | TSSOP-38 | FE | MP | 05-08-1865 | Yes |
| LT3752MPFE#PBF | TSSOP-38 | FE | MP | 05-08-1865 | Yes |
| LT3752MPFE#TRPBF | TSSOP-38 | FE | MP | 05-08-1865 | 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 | |
|---|---|---|---|---|---|---|
| LT3752EFE-1#PBF | TSSOP-38 | E | $4.84 | $3.39 | Yes | |
| LT3752EFE-1#TRPBF | TSSOP-38 | E | $3.45 | Yes | ||
| LT3752EFE#PBF | TSSOP-38 | E | $4.84 | $3.39 | Yes | |
| LT3752EFE#TRPBF | TSSOP-38 | E | $3.45 | Yes | ||
| LT3752HFE-1#PBF | TSSOP-38 | H | $5.71 | $4.00 | Yes | |
| LT3752HFE-1#TRPBF | TSSOP-38 | H | $4.06 | Yes | ||
| LT3752HFE#PBF | TSSOP-38 | H | $5.71 | $4.00 | Yes | |
| LT3752HFE#TRPBF | TSSOP-38 | H | $4.06 | Yes | ||
| LT3752IFE-1#PBF | TSSOP-38 | I | $5.30 | $3.71 | Yes | |
| LT3752IFE-1#TRPBF | TSSOP-38 | I | $3.77 | Yes | ||
| LT3752IFE#PBF | TSSOP-38 | I | $5.30 | $3.71 | Yes | |
| LT3752IFE#TRPBF | TSSOP-38 | I | $3.77 | Yes | ||
| LT3752MPFE-1#PBF | TSSOP-38 | MP | $14.29 | $10.00 | Yes | |
| LT3752MPFE-1#TRPBF | TSSOP-38 | MP | $10.06 | Yes | ||
| LT3752MPFE#PBF | TSSOP-38 | MP | $14.29 | $10.00 | Yes | |
| LT3752MPFE#TRPBF | TSSOP-38 | MP | $10.06 | 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 |
|---|---|---|---|
| DC1929A | LT3752EFE-1/ LT8311EFE Demo Board | 150V ≤ VIN ≤ 400V, VOUT = 12V @ 16.7A | $300.00 | |
| DC1994A | LT3752EFE/LT8311EFE Isolated Demo Board | 18V ≤ VIN ≤ 72V; VOUT: 12V @ 12A | $300.00 | |
| DC2175A | LT3752IFE/LT8311IFE Demo Board | Forward Converter with Sync Rectification, 9V ≤ VIN ≤ 36V; Vout = 12V @ 13A | $300.00 | |
| Buy Now | |||
Applications
- Offline and HV Car Battery Isolated Power Supplies
- 48V Telecommunication Isolated Power Supplies
- Industrial, Automotive and Military Systems
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Design Tools
LTspice
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Models for the following parts are available in LTspice:
LT3752
LT3752-1
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.
