Energy-Efficient, Accurate Primary-Side Regulation CV/CC Switcher for Adapters and Chargers
Figure 1. Typical Application – Not a Simplified Circuit.
Data Sheets
LinkSwitch-3 Data Sheet
Energy-Efficient, Accurate Primary-Side Regulation CV/CC Switcher for Adapters and Chargers
ECAD Models
Product Details
The LinkSwitch-3 family of ICs dramatically simplifies low power CV/CC charger designs by eliminating an optocoupler and secondary control circuitry. The device introduces a revolutionary control technique to provide very accurate output voltage and current regulation, compensating for transformer and internal parameter tolerances along with input voltage variations.
The device incorporates a 725 V power MOSFET, a novel ON/OFF control state machine, a high-voltage switched current source for self biasing, frequency jittering, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry onto a monolithic IC.
Product Highlights
Dramatically Simplifies CV/CC Converters
- Eliminates optocoupler and all secondary CV/CC control circuitry
- Eliminates all control loop compensation circuitry
Advanced Performance Features
- Compensates for transformer inductance tolerances, input line voltage variations, and cable voltage drop
- Very tight IC parameter tolerances using proprietary trimming technology
- Frequency jittering greatly reduces EMI filter cost
- Programmable switching frequency up to 85 kHz to reduce transformer size
- Minimum operation frequency fixed to improve transient load response
Advanced Protection/Safety Features
- Hysteretic thermal shutdown – automatic recovery reduces power supply returns from the field
- Meets high-voltage creepage requirements between DRAIN and all other pins both on the PCB and at the package
EcoSmart™– Energy Efficient
- Easily meets all global energy efficiency regulations with no added components
- No-load consumption at 230 VAC input with bias winding <30 mW
Green Package
- Halogen free and RoHS compliant package
Applications
Power Table
| Output Power (Watts)1,2,3,4 | ||
|---|---|---|
| Product5 | 90-264 VAC | |
| D (SO-8) Package | ||
| Adapter | Open Frame | |
| LNK6404D LNK6424D | 3.5 W | 4.1 W |
| LNK6405D LNK6415D LNK6425D | 4.5 W | 5.1 W |
| LNK6406D LNK6416D LNK6426D LNK6436D LNK6446D | 5.5 W | 6.1 W |
| LNK6407D LNK6417D LNK6427D | 7.5 W | 7.5 W |
| Product5 | K (eSOP) and E (eSIP) Packages | |
| Adapter | Open Frame | |
| LNK6407K LNK6417K LNK6427K | 8.5 W | 9 W |
| LNK6408K LNK6418K LNK6428K LNK6448K | 10 W | 10 W |
| LNK6408E LNK6418E LNK6428E LNK6448E | 10 W | 10 W |
Notes:
- Assumes minimum input DC voltage >90 VDC, KP ≥1 (Recommend KP ≥1.15 for accurate CC regulation), η >78%, DMAX <55%.
- Output power capability is reduced if a lower input voltage is used.
- Minimum continuous power with adequate heat sink measured at 50 °C ambient with device junction below 110 °C.
- Assumes bias winding is used to supply BYPASS pin.
- Package: D: SO-8C, E: eSIP-7C, K: eSOP-12B
Product Documents
Design Examples
Product Image
