Hybrid Step-Down Synchronous Controller
Features and Benefits
- Low Profile, High Power Density, Capable of 500W+
- Soft Switching: 99% Peak Efficiency and Low EMI
- VIN Max for Voltage Divider (2:1): 72V
- VIN Max for Voltage Doubler (1:2)/Inverter (1:1): 36V
- Wide Bias VCC Range: 6V to 72V
- Soft Startup into Steady State Operation
- 6.5V to 40V EXTVCC Input for Improved Efficiency
- Input Current Sensing and Overcurrent Protection
- Wide Operating Frequency Range: 100kHz to 1MHz
- Output Short-Circuit/OV/UV Protections with Programmable Timer and Retry
- Thermally Enhanced 28-Pin 4mm × 5mm QFN Package
The LTC7820 is a fixed ratio high voltage high power switched capacitor/charge pump controller. The device includes four N-channel MOSFET gate drivers to drive external power MOSFETs in voltage divider, doubler or inverter configurations. The device achieves a 2:1 step-down ratio from an input voltage as high as 72V, a 1:2 step-up ratio from an input voltage as high as 36V, or a 1:1 inverting ratio from an input voltage up to 36V. Each power MOSFET is switched with 50% duty cycle at a constant pre-programmed switching frequency. System efficiency can be optimized to over 99%. The LTC7820 provides a small and cost effective solution for high power, non-isolated intermediate bus applications with fault protection.
The LTC7820 switching frequency can be linearly programmed from 100 kHz to 1MHz. The device is available in a thermally enhanced 28-lead QFN package with some no-connect pins for high voltage compatible pin spacing.
- Bus Converters
- High Power Distributed Power Systems
- Communications Systems
- Industrial Applications
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 2543A is a high efficiency, high density, open loop charge pump (inductorless) DC/DC converter. This demo board is a voltage divider which achieves a 2:1 step-down ratio from an input voltage from 36V to 60V. The output voltage is a fixed ratio of half of the input voltage (VIN/2) and can supply a 10A load current. This demo board has the option to deliver a 20A maximum load with the addition of 15 chip capacitors.
Tools & Simulations
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.
Models for the following parts are available in LTspice:
LTC7820 Companion Parts
Recommended Related Parts
Product Selector Card (1)
Technical Articles (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.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.