company blog about ADI EV-DPS-PWRBD1Z 20A LTC3871 Power Evaluation Board For LT8740 Device Power Supply

ADI EV-DPS-PWRBD1Z 20A LTC3871 Power Evaluation Board For LT8740 Device Power Supply

Shenzhen Mingjiada Electronics Co., Ltd., as a professional electronic component supplier, now fully stocks ADI's high-performance power supply evaluation kit—the EV-DPS-PWRBD1Z power board. This evaluation board is specifically designed to complement the advanced LT8740 programmable device power supply, integrating dual LTC3871 controllers to provide engineers with a complete, efficient, and bidirectional 20A power solution.

EV-DPS-PWRBD1Z Core Components and Design Philosophy:

The core design objective of the EV-DPS-PWRBD1Z evaluation board is to deliver robust, flexible, and fully compatible power support for the LT8740 Programmable Device Power Supply.

Future-proof Programmable Device Power Supply (LT8740): The LT8740 is a highly integrated, high-performance dual-channel programmable device power supply from ADI. Each channel delivers up to ±2A (or ±2.25A, depending on specific model) drive current across an output voltage range up to 30V. Its core value lies in integrating current sense resistors, analogue-to-digital/digital-to-analogue converters (ADC/DAC), and a digital PID control loop. This enables precise programming, measurement, and clamping control of output voltage and current via a simple SPI or two-wire serial interface, making it ideal for ATE equipment demanding exceptional accuracy and automation.

Breakthrough Dual-Rail Bidirectional Power Architecture (EV-DPS-PWRBD1Z): To fully leverage the LT8740's four-quadrant capability (providing current while simultaneously sinking current), conventional solutions require two separate and costly bidirectional power supplies. The EV-DPS-PWRBD1Z innovatively employs a single-input, dual-output architecture, enabling a single bidirectional power supply to simultaneously generate both positive (VPOS) and negative (VNEG) voltage rails. Each rail possesses full source (supply) and sink (absorption) capability. This significantly simplifies system architecture, reduces costs, and enhances overall efficiency through internal, highly efficient current path management.

High-Performance PolyPhase® Controller (LTC3871): Each output of the EV-DPS-PWRBD1Z power board is driven by an LTC3871 controller. The LTC3871 for the positive voltage rail (VPOS) is configured as a buck converter, while the LTC3871 for the negative voltage rail (VNEG) is configured as a flyback buck-boost converter. The LTC3871 itself is a bidirectional buck or boost controller. Its symmetrical current limiting capability ensures each output rail can stably input or output approximately equal currents, forming the cornerstone for achieving efficient, stable bidirectional power delivery.

EV-DPS-PWRBD1Z Core Architecture and Key Technologies:

At the heart of the EV-DPS-PWRBD1Z are two ADI LTC3871 high-performance controllers. This multi-output synchronous bidirectional DC/DC controller is renowned for its flexibility and high efficiency, supporting a wide input voltage range from 4.5V to 38V.

Inverted Buck-Boost is pivotal for achieving negative voltage outputs. By redefining the standard buck converter's ground pin as the negative output and the original output pin as system ground, the circuit generates a negative output from a positive input. This topology enables the LTC3871 to operate flexibly in either buck or boost mode to accommodate varying voltage conversion requirements.

Bidirectional Energy Flow represents another significant highlight. When the evaluation board supplies power to the load, the controller operates in ‘source’ mode. However, when the voltage from an external power source (or device under test) exceeds the set value, the controller seamlessly switches to ‘sink’ mode, absorbing energy back into the system. This capability is crucial for testing scenarios such as short-circuit protection in power management ICs and battery charge/discharge cycles.

Key Features of EV-DPS-PWRBD1Z:

- Up to 20A continuous output capability: Both channels deliver up to 20A, providing ample power for evaluating the LT8740's performance under heavy loads or applications requiring expanded output current through parallel DPS channels.

Complete Source-Sink Functionality: A core advantage of this board. When connected external devices (such as batteries, capacitors, or other power sources) exceed the set voltage threshold, the power board automatically transitions to current sink mode, feeding energy back to the input. This feature is vital for testing scenarios requiring energy feedback, such as battery charging/discharging and motor braking.

Extensive Test Interfaces and Programmability: Multiple test points are integrated on-board, facilitating engineers' use of oscilloscopes, multimeters, and other tools to monitor voltage, current, and waveforms at all critical nodes. Furthermore, inheriting the programmable nature of the LTC3871 and LT8740, it supports setting voltage and current limits via external resistor networks or digital interfaces, delivering high design flexibility.

EV-DPS-PWRBD1Z Performance Specifications and Application Configuration:

The EV-DPS-PWRBD1Z designation incorporates its key performance characteristics: ‘1Z’ denotes its specific variant, while ‘20A’ indicates the continuous output capability per output rail.

This EV-DPS-PWRBD1Z evaluation board possesses defined electrical specifications and requires specific peripheral equipment to achieve full performance.

Key Electrical Specifications:

Input Voltage: 20V to 26V, with a recommended nominal operating voltage of 24V.

Output Voltage: VPOS = +17.5V, VNEG = -17.5V (both referenced to ground).

Output current: 20A continuous per rail, with peak currents up to 22A.

Equipment required for system setup:

To fully evaluate and utilise the EV-DPS-PWRBD1Z power board, engineers should prepare a compact laboratory environment, ideally comprising the following equipment:

DC power supply: Minimum output voltage of 30V and minimum output current of 30A.

Electronic load: 800W power rating, supporting 0V to 60V range.

Oscilloscope: Minimum 500MHz bandwidth, 2 to 4 channels.

Digital multimeter: Such as HP34401 or equivalent precision model.

Connection cables: 18AWG or thicker gauge, fitted with ring terminals or crocodile clips.

Core evaluation subject of EV-DPS-PWRBD1Z: LT8740 device power supply

The ultimate service target of EV-DPS-PWRBD1Z is ADI's LT8740 programmable device power supply. This highly integrated dual-channel DPS delivers ±2A (or ±2.25A) drive current per channel across an output range up to 30V.

The LT8740's core strengths lie in its ‘fully integrated’ and ‘high-precision’ design. It incorporates an internal current sense resistor, analogue-to-digital/digital-to-analogue converters, a digital PID control loop, and Silent Switcher® architecture power switches. This enables direct digital control for precise voltage (FV) and current (FI) output and measurement.

Together, they form an ideal evaluation system: the EV-DPS-PWRBD1Z serves as an energy reservoir, delivering powerful, clean, and controllable bidirectional high currents; the LT8740 acts as a precision control and measurement front-end, directly interfacing with the device under test to perform nanoamp-level current measurements and execute complex test sequences. Through simple parallel connection, this system can be easily scaled to meet higher current demands.

Typical Applications for EV-DPS-PWRBD1Z:

The EV-DPS-PWRBD1Z paired with the LT8740 offers an excellent, ready-to-use solution for tackling complex power management challenges.

Automated Test Equipment (ATE) Development: This represents its most direct application domain. In semiconductor testing and circuit board functional verification, test systems require programmable precision voltage and current delivery to diverse pins alongside accurate response measurement. This evaluation kit provides stable, efficient bidirectional power for DPS boards within ATE systems, accelerating test platform development.

Precision Device Powering and Characterisation: Suitable for evaluating performance metrics such as power sensitivity, power consumption, and start-up characteristics in precision analogue devices including operational amplifiers, data converters (ADC/DAC), and sensors. Its low-noise operation and precise programmability are critical.

High-Reliability Power System Prototyping: Power systems in industrial control, communications infrastructure, aerospace, and similar domains demand exceptional reliability and flexibility. Engineers can utilise this evaluation board to rapidly prototype, validate the feasibility of multi-rail, bidirectional, high-current power architectures, and optimise control algorithms.

Mingjiada Electronics maintains long-term supply of other ADI evaluation board components, including but not limited to the following models:

EV-ADUM7701-8FMCZ

EVAL-AD7983-PMDZ

AD9135-FMC-EBZ

AD9139-DUAL-EBZ

AD9695-625EBZ

EV-AD74412RSDZ

EVAL-AD7685SDZ

EVAL-10BT1L-MCS-AZ

EVAL-10BT1L-MCS-BZ

EVAL-AD4858FMCZ

EVAL-AD4129-8WARDZ

MAX40109ITEVSYS1

EVAL-AD45335SDZ

EVAL-AD5675RARDZ

EVAL-AD5686RARDZ