LTC7851
RECOMMENDED FOR NEW DESIGNSQuad Output, Multiphase Step-Down Voltage Mode DC/DC Controller with Accurate Current Sharing
- Part Models
- 8
- 1ku List Price
- Starting From $5.86
Overview
- 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
The LTC7851/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.
Applications
- High Current Distributed Power Systems
- DSP, FPGA and ASIC Supplies
- Datacom, Telecom and Computing Systems
Documentation
Data Sheet 1
User Guide 1
Design Note 1
Technical Articles 2
Video 1
Brochure 1
Press Release 1
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LTC7851EUHH#PBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851EUHH#TRPBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851EUHH-1#PBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851EUHH-1#TRPBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851IUHH#PBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851IUHH#TRPBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851IUHH-1#PBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) | ||
| LTC7851IUHH-1#TRPBF | 58-Lead QFN (5mm x 9mm x 0.75mm w/ EP) |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
| Parts | Product Life Cycle | Description |
|---|---|---|
| Ideal Diodes and PowerPath Controllers 1 | ||
| LTC4370 | RECOMMENDED FOR NEW DESIGNS | Two-Supply Diode-OR Current Balancing Controller |
| Power System Management (PSM) & Sequencers 1 | ||
| LTC2975 | RECOMMENDED FOR NEW DESIGNS | 4-Channel PMBus Power System Manager Featuring Accurate Input Current and Energy Measurement |
| Parts | Product Life Cycle | Description |
|---|---|---|
| LTC3861 | LAST TIME BUY | Dual, Multiphase Step-Down Voltage Mode DC/DC Controller with Accurate Current Sharing |
Tools & Simulations
LTspice 2
- LTC7851/LTC4449 Demo Circuit - High Current, Quad Output Synchronous Buck Converter with Discrete Gate Drivers and MOSFETs (7-14V to 1.8V, 1.5V, 1.2V, 1.0V @ 30A)
- LTC7851/LTC4449 Demo Circuit - 4-Phase Converter with Discrete Gate Drivers and MOSFETs (7-14V to 1.2V @ 120A)
Models for the following parts are available in LTspice:
- LTC7851
- LTC7851-1
LTpowerCAD 2
- LTC7851/LTC4449 Project - Quad Output, Multiphase Step-Down Voltage Mode DC/DC Controller (7-14V to 1.8V, 1.2V & 1V @ 30A)
- LTC7851-1/LTC4449 Project - Quad Output, Multiphase Step-Down Voltage Mode DC/DC Controller (7-14V to 1.8V, 1.5V, 1.2V & 1V @ 30A)
Design tools for the following parts are available in LTpowerCAD:
- LTC7851
- LTC7851-1
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
Evaluation Kits
LTC7851EUHH Demo Board | Single Output, 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; VOUT1 = 1.2V @ 120A
Resources
LTC7851EUHH Demo Board | Single Output, 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; VOUT1 = 1.2V @ 120A
Resources
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
Resources
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
Resources
LTC7851EUHH Demo Board | Dual Output, 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; VOUT1 = 1.8V @ 60A, VOUT3 = 1.2V @ 60A
Resources
LTC7851EUHH Demo Board | Dual Output, 4-Phase Voltage Mode Buck Controller, 7V ≤ VIN ≤ 14V; VOUT1 = 1.8V @ 60A, VOUT3 = 1.2V @ 60A