DocumentationDatasheet
Reliability Data
LT Journal
Press Release
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Features
- N-Channel Synchronous Rectifier MOSFET Driver
- Programmable Timeout Protection
- Reverse Inductor Current Protection
- Pulse Transformer Synchronization
- Wide VCC Supply Range: 4.5V to 11V
- 15ns Rise/Fall Times at VCC = 5V, CL = 4700pF
- Undervoltage Lockout
- Small SO-8 Package
Typical Application
Description
The LTC®3900 is a secondary-side synchronous rectifier driver designed to be used in isolated forward converter power supplies. The chip drives N-channel rectifier MOSFETs and accepts pulse sychronization from the primary-side controller via a pulse transformer.
The LTC3900 incorporates a full range of protection for the external MOSFETs. A programmable timeout function is included that disables both drivers when the synchronization signal is missing or incorrect. Additionally, the chip senses the output inductor current through the drainsource resistance of the catch MOSFET, shutting off the MOSFET if the inductor current reverses. The LTC3900 also shuts off the drivers if the supply voltage is too low.
SO-8
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC3900ES8#PBF | SO | 8 | E | $3.57 | $2.50 |
| LTC3900ES8#TRPBF | SO | 8 | E | $2.56 | |
| LTC3900HS8#PBF | SO | 8 | H | $4.11 | $2.88 |
| LTC3900HS8#TRPBF | SO | 8 | H | $2.94 | |
| LTC3900IS8#PBF | SO | 8 | I | $3.70 | $2.59 |
| LTC3900IS8#TRPBF | SO | 8 | I | $2.65 | |
| LTC3900MPS8#PBF | SO | 8 | MP | $10.00 | $7.00 |
| LTC3900MPS8#TRPBF | SO | 8 | MP | $7.06 | |
| LTC3900ES8 | SO | 8 | E | $7.14 | $5.00 |
| LTC3900ES8#TR | SO | 8 | E | $5.12 |
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 |
|---|---|---|---|
| DC1317A-C | LT1952EGN-1/LTC3900 Demo Board | Active Reset, Vin=18V-72V Vout=12V @ 10A | $175.00 | |
| DC1317A-G | LT1952EGN-1/LTC3900 Demo Board | Active Reset, Vin=9V-36V Vout=12V @ 5A | $175.00 | |
| DC677A | LT1952-1EGN-1, LTC3900ES Demo Board | Vin=36V-75V, Vout=3.3V @ 50A | Contact Factory | |
| DC968A-A | LT1952EGN-1, LTC3900CS8, LT4430ES6 Demo Board | Vin=34V-75V Vout=3.3V @ 30A | $150.00 | |
| DC968A-B | LT1952EGN-1, LTC3900CS8, LT4430ES6 Demo Board | Vin=18V-36V, Vout=5V @ 20A | $175.00 | |
| DC968A-C | LT1952EGN-1, LTC3900CS8, LT4430ES6 Demo Board | Vin=36V-75V, Vout=12V @ 12A | $150.00 | |
| DC968A-D | LT1952EGN-1, LTC3900CS8, LT4430ES6 Demo Board | Vin=36V-75V, Vout=28V @ 4A | $175.00 |