VideosDocumentationDatasheet
Reliability Data
Article
- Next Generation Router & Switch Platforms Demand Flexible DC/DC Controllers
- Smart & Flexible High Current DC/DC Controllers Simplify Power Supplies in Telecom & Datacom Systems
Press Release
cad_symbol
Ad
Features
- Operates with Power Blocks, DrMOS or External Gate Drivers and MOSFETs
- Voltage Mode Control with Accurate Current Sharing
- ±0.75% 0.6V Voltage Reference
- Quad Differential Output Voltage Sense Amplifiers
- Multiphase Capability
- Phase-Lockable Fixed Frequency 250kHz to 2.25MHz
- Lossless Current Sensing Using Inductor DCR or Precision Current Sensing with Sense Resistor or DrMOS with Integrated Current Sensing
- VCC Range: 3V to 5.5V
- VOUT Range: 0.6V to VCC – 0.5V
- Power Good Output Voltage Monitor
- Output Voltage Tracking Capability with Soft-Start
- Available in 58-Lead 5mm × 9mm QFN Package
Typical Application
Description
The LTC®7851/LTC7851-1 are quad output multiphase synchronous step-down switching regulator controllers that employ a constant frequency voltage mode architecture. They maintain excellent current balance between channels when paralleled with their internal current sharing loop. Lossless DCR or a low value RSENSE is used for output current sensing. Multiple LTC7851/LTC7851-1 devices can be used for high phase count operation.
A very low offset, high bandwidth error amplifier, combined with remote output voltage sensing, provides excellent transient response and output regulation. The LTC7851/ LTC7851-1 operates with a VCC supply voltage from 3V to 5.5V and is designed for step-down conversion with VIN from 3V to 27V* and produces an output voltage from 0.6V to VCC – 0.5V.
The LTC7851-1 is identical to the LTC7851 except it has a lower current sense amplifier gain, making it ideal for DrMOS devices with internal current sense.
5x9 QFN-58
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC7851IUHH#TRPBF | QFN | 58 | I | $7.03 | $4.94 |
| LTC7851EUHH-1#TRPBF | QFN | 58 | E | $6.16 | $4.33 |
| LTC7851IUHH-1#PBF | QFN | 58 | I | $6.97 | $4.88 |
| LTC7851IUHH-1#TRPBF | QFN | 58 | I | $7.03 | $4.94 |
| LTC7851EUHH-1#PBF | QFN | 58 | E | $6.10 | $4.27 |
| LTC7851IUHH#PBF | QFN | 58 | I | $6.97 | $4.88 |
| LTC7851EUHH#PBF | QFN | 58 | E | $6.10 | $4.27 |
| LTC7851EUHH#TRPBF | QFN | 58 | E | $6.16 | $4.33 |
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 |
|---|---|---|---|
| DC2380A-A | LTC7851EUHH Demo Board | 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; Vout1 = 1.8V @ 30A, Vout2 = 1.5V @ 30A, Vout3 = 1.2V @ 30A, Vout4 = 1V @ 30A | $250.00 | |
| DC2380A-B | LTC7851EUHH Demo Board | Dual Output, 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; Vout1 = 1.8V @ 60A, Vout3 = 1.2V @ 60A | $300.00 | |
| DC2380A-C | LTC7851EUHH Demo Board | Single Output, 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; Vout1 = 1.2V @ 120A | $400.00 |