ADI公司的AD8452是具有透明和自動切換特性的 CC 和 CV 電池測試和化成模塊,組合了精密模擬前端(AFE)控制器和開關電源(SMPS),脈寬調制器(PWM)驅動器,精密儀表放大器(in-amp)測量電池充電/放電電流精度優于±0.1%,電流感應儀器放大器增益66 V/V,電壓感應差分放大器增益0.4 V/V,失調電壓漂移<0.6 μV/℃,增益漂移<3 ppm/℃,同步輸出或輸入,相移可調,可編程軟啟動,主要用在電池化成和測試,具有循環效能的高效電池測試系統和電池調理(充電和放電)系統.本文介紹了AD8452主要特性,框圖,應用電路,評估板AD8452-EVALZ主要特性,框圖,電路圖,材料清單和PCB設計圖.此外還介紹了相應的AD8452電池測試和化成評估板(電源板和模擬接口板)主要特性,框圖,電路圖,材料清單和PCB設計圖.

The AD8452 combines a precision analog front-end controller and switch mode power supply (SMPS), pulse-width modulator (PWM) driver into a single silicon platform for high volume battery testing and formation manufacturing. A precision instrumentation amplifier (in-amp) measures the battery charge/ discharge current to better than ±0.1% accuracy, while an equally accurate difference amplifier measures the battery voltage. Internal laser trimmed resistor networks establish the in-amp and difference amplifier gains (66 V/V and 0.4 V/V, respectively), and stabilize the AD8452 performance across the rated operating temperature range. Desired battery cycling current and voltage levels are established by applying precise control voltages to the ISET and VSET inputs. Actual charge and discharge current levels are sensed (usually by a high power, highly accurate shunt resistor) whose value is carefully selected according to system parameters. Switching between constant current (CC) and constant voltage (CV) loop integration is instantaneous, automatic, and completely transparent to the observer. A logic high at the MODE input selects the charge or discharge mode (high for charge, low for discharge). The AD8452 simplifies designs by providing excellent performance, functionality, and overall reliability in a space saving 48-lead, 7 mm × 7 mm × 1.4 mm LQFP package rated for operation at temperatures from ?40℃ to +85℃.

AD8452主要特性:

CC and CV battery test and formation modes with transparent and automatic switchover, for systems of 20 Ah or less
Precise measurement of voltage and current
Independent feedback control blocks
Highly accurate, factory trimmed instrumentation and differential amplifiers In-amp for current sense gain: 66 V/V Difference amplifier for voltage sense gain: 0.4 V/V
Stable over temperature: offset voltage drift <0.6 μV/℃ (maximum)
Gain drift: <3 ppm/℃ (maximum) Current sense CMRR: 120 dB minimum
Popular SMPS control for charge/discharge
High PWM linearity with internal ramp voltage
50 kHz to 300 kHz user controlled switching frequency
Synchronization output or input with adjustable phase shift
Programmable soft start

AD8452應用:

Battery formation and testing
High efficiency battery test systems with recycle capability
Battery conditioning (charging and discharging) systems

圖1.AD8452功能框圖

圖2.AD8452詳細框圖

圖3.AD8452鋰電池和測試信號通路圖

圖4.AD8452鋰電池測試和化成系統完整信號通路圖

AD8452通用評估板AD8452-EVALZ

The AD8452-EVALZ is a platform for the AD8452, designed for investigation of the AD8452 analog and pulse-width modulation (PWM) features and performance without the added complica- tions of a driver and/or switch mode power supply (SMPS) design. For convenience, a precision 5 V reference IC and four trim pots are built in to the evaluation board, for driving the battery current and voltage ISET and VSET inputs. All device pins are accessible with test loops or probe landings. At the same time, the AD8452-EVALZ has the flexibility to interface and drive a typical half bridge inductor input SMPS with output levels in the 1 A to 15 A range. SMPS and associated components are specified and sourced by the user. The AD8452 is intended for use as the core controller for commercial battery test and formation systems. Its advanced miniaturization and extraordinarily high level of analog precision meet the challenge of mass production of high energy density storage lithium ion packs for transportation and energy storage in homes.

評估板AD8452-EVALZ主要特性:

Pin accessible, standalone AD8452
Simplified operation: connect a power supply and scope and start looking at waveforms
On-board precision 5 V reference included for accurate gain measurements
Factory tested
Four optional control loops available but not necessary for operation; may be bypassed as desired
Safe: only low power circuitry is present; no accidental power discharges

圖5.評估板AD8452-EVALZ外形圖

圖6.評估板AD8452-EVALZ測試建立圖

圖7.評估板AD8452-EVALZ電路圖
評估板AD8452-EVALZ材料清單:

圖8.評估板AD8452-EVALZ PCB絲印圖

圖9.評估板AD8452-EVALZ PCB頂層(元件面)布局圖

圖10.評估板AD8452-EVALZ PCB設計圖:層2-地

圖11.評估板AD8452-EVALZ PCB設計圖:層3-電源

圖12.評估板AD8452-EVALZ PCB設計圖:底層-銅

AD8452電池測試和化成評估板

The AD8452 system demo evaluation kit is a recommended starting point for users building battery formation and test equipment based on the Analog Devices, Inc., AD8452 precision analog front end and pulse-width modulation (PWM) controller. The evaluation kit includes an analog interface board and a power module board.

In addition to the AD8452, the analog interface board also includes an AD5689R 16-bit, precision digital-to-analog converter (DAC) to set the current and voltage set points, and an AD7173-8 24-bit, Σ-Δ analog-to-digital converter (ADC) to monitor the battery voltage and current.

The analog interface board includes built-in voltage regulators so that it can be powered either from the bus power inputs or directly from a 15 V dc supply through a screw terminal connector.

The analog interface board connects to the Analog Devices System Demonstration Platform (SDP-S) through a 120-pin connector. The SDP-S board connects to the user interface software through the USB port, allowing the user to set the current and voltage set point as well as the mode of operation (charge or discharge). In addition, the user can monitor the battery voltage and current by reading the data output from the AD7173-8.
The analog interface board connects to the power module board through three multipin headers. This modular approach allows the user to design and test their own power module boards, designed for the current output range in their end applications, with the analog interface board of this reference design.

The standard power module board supports charge and discharge currents of up to 10 A. It includes the power metal-oxide semiconductor field effect transistors (MOSFETs), the inductor, and the input and output capacitors required to implement a buck or boost regulator, depending on the operating mode.

Full specifications of the AD8452 are available in the product data sheet, which must be consulted in conjunction with this user guide when working with the evaluation kit.

AD8452電池測試和化成評估板主要特性:

Fully functional Li-Ion cell formation and testing similar to real-world manufacturing equipment
Ability to charge and discharge batteries under constant current and constant voltage control
Energy recycling from discharging battery into a dc bus
Full featured system evaluation board based on the AD8452
PC software for control and monitoring of system parameters
Compatible with the System Demonstration Platform, SDP-S (EVAL-SDP-CS1Z)

AD8452電池測試和化成評估板包括:

Analog interface board
Power module board (10 V to 20 V dc operating range)
SDP-S board for data transfer to PC
Standard USB A to Mini-B USB cable
Printed user guide
Evaluation kit software CD

圖13.AD8452電池測試和化成評估板外形圖:上:電源模塊;下:模擬接口板

圖14.AD8452電池測試和化成評估板系統框圖

圖15.AD8452電池測試和化成評估板電源模塊電路圖
電源模塊材料清單:

圖16.電源模塊PCB設計圖:頂層絲印

圖17.電源模塊PCB設計圖:頂層布局

圖18.電源模塊PCB設計圖:層2布局

圖19.電源模塊PCB設計圖:層3布局

圖20.電源模塊PCB設計圖:底層布局

圖21.電源模塊PCB設計圖:底層絲印

圖22.電源模塊PCB綜合設計圖

圖23.模擬接口板電路(1):電源連接器和輔助電源

圖24.模擬接口板電路(2):AD8452和補償網絡

圖25.模擬接口板電路(3):ADC,DAC和SDP連接器
模擬接口板材料清單:

圖26.模擬接口板PCB設計圖(1):絲印圖

圖27.模擬接口板PCB設計圖(2):頂層布局圖

圖28.模擬接口板PCB設計圖(3):層2

圖29.模擬接口板PCB設計圖(4):層3

圖30.模擬接口板PCB設計圖(5):底層

圖31.模擬接口板PCB設計圖(6):底層絲印

圖32.模擬接口板PCB設計圖(7):綜合圖