functional test automotive seminar in mexico

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Functional Test for Automotive Electronics Manufacturing Presented by: Rodrigo Cantu Agilent Technologies

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Page 1: Functional Test Automotive Seminar in Mexico

Functional Test

for Automotive Electronics

Manufacturing Presented by:

Rodrigo Cantu

Agilent Technologies

Page 2: Functional Test Automotive Seminar in Mexico

Agenda

1. Automotive Market Overview

2. Automotive Electronics Functional Test

4. Agilent Functional Test Solutions

6. Question & Answer (Q&A) Session

3. Functional Test Challenges

5. HEV/EV – Functional test & Solutions

Page 3: Functional Test Automotive Seminar in Mexico

a

b

c

d

j

l k

e

f

g

h

i

Automotive Electronics in Cars Today

Body Electronics -

Comfort/Convenience

Powertrain & Hybrid

Safety and

Driver Assistance

Infotainment &

Communications

a. Adaptive Cruise Control

b. Collision Warning

c. Tire pressure monitoring

d. Audio Systems

e. Multimedia Systems

f. Rear Seat Entertainment

j. Instrument Cluster

k. Remote keyless entry

l. Climate Control

g. Engine management

h. Braking System

i. Power Steering

Air Conditioning

System

Page 4: Functional Test Automotive Seminar in Mexico

Automotive Market and Applications

Powertrain and Hybrid Systems Body Electronics

Safety and Chassis Infotainment and Telematics

Gasoline and Diesel Engine Management

Automatic Gearbox and Transmission

Hybrid Drive Train

Convenience and Comfort ECU – Lighting,

Climate Control, Memory Seats, etc.

Driver Assistance ECU – Night Vision, Cruise

Control, Park/Reverse Assist, etc.

Security ECU – Remote Keyless Entry (RKE)

Airbag ECU – Conventional and Adaptive)

Braking Systems – ABS and Traction Control

Tire Pressure Monitoring Systems (TPMS)

Collision Avoidance Electronics – DSRC

In-Car Entertainment – Radio, DAB/DVB, etc.

In-Car Networking – Bluetooth, WiMax, etc.

Telematics – GPS Navigation

Instrument Cluster – Dashboard

Page 5: Functional Test Automotive Seminar in Mexico

The Next Key Agenda for Automotive Hybrid and Electric Vehicles

Page 6: Functional Test Automotive Seminar in Mexico

Agenda

1. Automotive Market Overview

2. Automotive Electronics Functional Test

4. Agilent Functional Test Solutions

6. Question & Answer (Q&A) Session

3. Functional Test Challenges

5. HEV/EV – Functional test & Solutions

Page 7: Functional Test Automotive Seminar in Mexico

Remote Keyless Entry (RKE)

RF

Receiver

Page 8: Functional Test Automotive Seminar in Mexico

Remote Keyless Entry (RKE transmitter) – functional

test

Frequency Counter

Spectrum Analyzer

Voltage / Current

Source

Measurement

Instrument

Stimulate &

Measurement

Signal

Power Supplies

Power Management

Battery leakage

current

Power Analysis, e.g:

output amplitude,

center frequency

Response time

Page 9: Functional Test Automotive Seminar in Mexico

Remote Keyless Entry (RKE receiver) – functional test

Arbitrary Waveform Generator

CAN/LIN Transceiver

Communication

Power Supplies

Power Management

Stimulus Signal

Vector Signal Generator

Frequency Counter

Measurement

Instrument

As transmitter ( generate

FSK/ ASK modulate data)

Immobilizer testing, e.g:

RFID simulate charge cycle,

ignition

Time elapse

Page 10: Functional Test Automotive Seminar in Mexico

Infotainment System

Microcontroller

RF

Receiver

Power

Amplifier

Power

Supply

CAN

Transceiver

Power Management Communication

Input RF signals

CAN/LIN Transceiver Vehicle Battery

Radio station tower

Bluetooth devices

GPS Satellite

Multi Channel

Loudspeaker

Output Audio Signal

Page 11: Functional Test Automotive Seminar in Mexico

Infotainment System – functional test

Microcontroller

RF

Receiver

Power

Amplifier

Power

Supply

CAN

Transceiver

Power Management Communication

Input RF signals

CAN/LIN Transceiver Power Supply

Vector Signal

Generator

Wireless Connectivity

Test Set

Audio Generator +

Analyzer

Measurement

instrument

Generate modulated

signal, e.g: GPS,

FM/AM/RDS

Bluetooth test, e.g:

pairing, headset

Power level

Frequency response

THD+N

SINAD

IMD

Crosstalk

Page 12: Functional Test Automotive Seminar in Mexico

Anti-Lock Braking System

Microcontroller

High Side

Switch

Low Side

Switch

Sensor

Receiver

CAN

Transceiver

Voltage

Regulator

Power Management Communication

CAN/LIN Transceiver Vehicle Battery

Input Sensor

Wheel Speed Sensor

Pump Motor

Output Sensor

Valves

Page 13: Functional Test Automotive Seminar in Mexico

Simulate and

Measurement

Signal

Voltage / Current

Source

Anti-Lock Braking System – functional test

Microcontroller

High Side

Switch

Low Side

Switch

Sensor

Receiver

CAN

Transceiver

Voltage

Regulator

Power Management Communication

CAN/LIN Transceiver Power Supply

Sensor Input

Arbitrary Waveform

Generator

Measurement

Instrument

Digital

Multimeter

Digitizer

Wheel slippage

detection

Crosstalk

Flyback voltage

Leakage current

Saturation voltage

Saturation voltage

Flyback voltage

Page 14: Functional Test Automotive Seminar in Mexico

Body Control Modules (BCM)

Microcontroller

High Side

Switches

Low Side

Switches

H-Bridges

Sensor Inputs

Break Pedal Sensor

Wheel speed sensor

Throttle Plate Sensor

Radar Sensor

Actuators

Throttle Actuator

Switch

Monitoring

CAN/LIN

Transceiver

Power

Supply

Power Management

CAN/LIN Transceiver

Communication

Brake Actuators

Vehicle Battery

Page 15: Functional Test Automotive Seminar in Mexico

Body Control Modules (BCM) – Functional Test

Sensor Inputs

simulated by Stimulus

Instrumentation

Actuators simulated

by Loads and output

are measured

Power Management

CAN/LIN Transceiver

Communication

Power Supplies

Device Under Test

(ECU)

Arbitrary Waveform Generator

Digital Analog

Converter

Voltage/ Current

Source

Digital

Multimeter

Frequency Counter

Data Acquisition Unit

Leakage Current

High Side Driver

Low Side Driver

Connectivity

Power On

Analog Input

Digital Input

Page 16: Functional Test Automotive Seminar in Mexico

Engine Control Modules (ECM)

Microcontroller

CAN/LIN

Transceiver

Power

Supply

Input

Sensor Output

Actuators Crankshaft Position

Sensor

Oxygen Sensor

Mass Air Injection

Sensor

Radar Sensor

Throttle Air Bypass

Solenoid

Fuel Injector System

EGR Shutoff Solenoid

Sensor Inputs Actuators

Power Management

CAN/LIN Transceiver

Communication

Vehicle Battery

Page 17: Functional Test Automotive Seminar in Mexico

Engine Control Modules (ECM) – functional test

Microcontroller

CAN/LIN

Transceiver

Power

Supply

Input

Sensor Output

Actuators

Stimulus

Instrumentations

Actuators

simulated by

Loads and output

are measured

Power Management

CAN/LIN Transceiver

Communication

Arbitrary Waveform

Generator

Voltage/

Current

Source

Digital to Analog

Converter

Power Supplies

Digital

Multimeter

Frequency Counter

Data Acquisition Unit

Open/Short

Power On

Analog Input

Digital Input

Starter Key

Knock Sensor

High side driver

Low side driver

Leakage current

Page 18: Functional Test Automotive Seminar in Mexico

DUT-Assisted (Simulation) Testing Concept

Sensor Inputs

simulated by Stimulus

Instrumentation

Actuators simulated

by Loads and output

are measured

Power Management

CAN/LIN Transceiver

Communication

Power Supplies

Device Under Test

(ECU)

Arbitrary Waveform Generator

Digital Analog

Converter

Voltage/ Current

Source Digital

Multimeter

Frequency Counter

Data Acquisition Unit

High

Current

Relays

Relays for Input

Conditioning

Page 19: Functional Test Automotive Seminar in Mexico

Signal Routing and Load Simulation

Power Supply

Measurement

Instrumentations

DMM Frequency

Counter

Microcontroller

Communication Power

Management

Input

Conditioning Output

Drivers

ECU

Switching Unit Stimulus

Instrumentations

Arbitrary

Waveform

Generator DAC Signal

Routing

Load

Simulation

Page 20: Functional Test Automotive Seminar in Mexico

How We Test the ECU Inputs?

Input Conditioning: - Switch High (with or without loads)

- Switch Low (with or without loads)

- Bridge Load Connections

Page 21: Functional Test Automotive Seminar in Mexico

How We Test the ECU Outputs?

Output Load Simulation: - Pull-Up (with or without loads)

- Pull-Down (with or without loads)

- Bridge Load Connections

Page 22: Functional Test Automotive Seminar in Mexico

How is UUT flashing done at functional test?

UUT Power

Supplies

Controller

(IPC)

AUX Power

Supplies

Switching

Resources

Others (e.g. Functional Test)

Platform support (e.g. sensors,

pneumatic lock,

electricity safety)

System

Flash device(s)

Fixture (base)

Aux. Equipment

Sensors,

Grounding

UUT(s)

UUT adapter(s)

UUT(s) UUT(s)

Page 23: Functional Test Automotive Seminar in Mexico

Flashing Station Test System Architecture

Power

Supplies

Switching

Modules

UUT Power

Supplies

Controller

(IPC)

AUX Power

Supplies

Switching

Resources

Others (e.g. Functional Test)

System

Functional

Test

Main

Controller

Page 24: Functional Test Automotive Seminar in Mexico

Agenda

1. Automotive Market Overview

2. Automotive Electronics Functional Test

4. Agilent Functional Test Solutions

6. Question & Answer (Q&A) Session

3. Functional Test Challenges

5. HEV/EV – Functional test & Solutions

Page 25: Functional Test Automotive Seminar in Mexico

“Functional Testing is as per customer requirement”

• Customer gives free will to how functional testing is performed

• Understands Pass / Fail…

“Understands importance of Functional Test but need expertise”

• Realizes that good functional test is essential to better yield, quality, throughput…

• No expertise in production for functional testing / test development

“Team has no bandwidth to cover end of line testing”

• Interested to work with external parties for functional testing implementation

• Need expert advice and hardware to make functional test a success

Functional Test Challenge #1 – Functional Test, Need Help?

Page 26: Functional Test Automotive Seminar in Mexico

Functional Test Challenge #2 – Test Development Problems

Customized Cables

Self Designed

Connections/Circuits

Instruments

Cost $$$

Page 27: Functional Test Automotive Seminar in Mexico

We take these worries away from you!

Full range of Agilent

Instruments

Standard

Switch & Load Modules

Standard Design

Interconnect

Standard Cables

System built for

Automotive Tests

Software

Integration through

TestExec SL

Global

uncompromised

support

Agilent

Standardization

Page 28: Functional Test Automotive Seminar in Mexico

Toyota recalled 8 million cars in total from 2008 to 2009

• Unwanted acceleration problems ( at least 58 crashes reported in US tied to this)

• NASA and NHTSA investigated found problems within electronic throttle control

Ford recalled 2.1 million trucks in 2011

• Airbags go off without warning

• Root cause, wiring placement caused short circuit triggering air bag blow off

General Motors recalled 1.4 million vehicles in 2010

• Fire Hazard problem from the heated wind shield washer fluid system

• Short Circuit in board causes ground wire to overheat and lead to fire

Functional Test Challenge #3 – Are you struggling with them?

Most problems when drilled down, came to one common

answer: “Not tested / Test Not Covered / Not Enough

Coverage”

Page 29: Functional Test Automotive Seminar in Mexico

Or do you want to get to the next ADVANCE Level?

We can help you!

Areas: Test Methodologies, Quality & Test Coverage

Technical Know How

for Automotive Functional

Test

Want to improve

your test coverage

and confidence?

Want to make the

best out of your

functional test?

Page 30: Functional Test Automotive Seminar in Mexico

How we help you to be successful?

Maverick Test: Achieve wider test coverage, better test confidence

Scenario: Not all pins are covered during a test, how do you know if there are

unwanted/unknown “remnant signals” or cross talks happening?

3ms

3ms

3ms

3ms

3ms

3ms

3ms

3ms

Agilent

M9216A

Agilent

M9216A

P01

P02

P03

P04

P05

P06

P07

P08

P09

P10

P11

P12

P13

P14

P15

P16

3ms

3ms

3ms

3ms

3ms

3ms

3ms

3ms

T (ms)

Pin No.

Pin No.

T (ms) Pins under monitoring

Pins under test

DUT

14V

0V

14V

0V

P09

P10

P11

P12

P13

P14

P15

P16

Monitored Pins Expected State

0V

0V

0V

0V

0V

0V

14V

V

T (ms)

0V

3ms

Page 31: Functional Test Automotive Seminar in Mexico

Agenda

1. Automotive Market Overview

2. Automotive Electronics Functional Test

4. Agilent Functional Test Solutions

6. TS-8900 System Demonstration

7. Question & Answer (Q&A) Session

3. Functional Test Challenges

5. HEV/EV – Functional test & Solutions

Page 32: Functional Test Automotive Seminar in Mexico

Automotive FMT System Architecture

System Controller

(Software & IO)

Measuring/Stimulus

Instrumentation

Power Sources

Signal/Load

Switching

Mass Interconnect Device Under Test

(DUT)

DUT-Specific

Connections

Analog Digital Power In

terf

aces:

PX

I, L

XI,

GP

IB

Serial Communication

Page 33: Functional Test Automotive Seminar in Mexico

Agilent Functional Systems

High Coverage &

Performance System

• Body Electronics

• Engine Control

• PXI-Based

• Parallel Test Method

U8972A

Mid-Size Test System

• ABS Sensors,

• Climate Control

• Tire Pressure

Monitoring (TPMS),

• Instrument Clusters

Compact Test System

• RKE

• Flashing

• Instrument Clusters

TS-5040

High Performance

System

• Body Electronics

• Engine Control

• VXI-Based

Instruments

TS-5400

TS-5020

New

Page 34: Functional Test Automotive Seminar in Mexico

U8972A (Venturi S3) – System Architecture

Agilent PXI Instruments &

Chassis Switch Load Unit Modular Power Supplies Macpanel Blocks & Cabling

U8972A

CORE

N3300 E-Load

1. 2.0m rack with solid door and extractor fan

2. 3-Phase only PDU with EMO switch

3. Power Distribution Unit (PDM)

4. Thermistor

5. IPC backplane, CPU i5-2400, RAM 4GB, HDD 250GB

6. Windows 7, Agilent IO, TestExec SL 7.1, TS-5000 7.1

7. PXI-based instrumentation

8. 210 pin & 64 hi-power ICA blocks & cabling

9. N3300A eLoad mainframe & modules

10. 1kW and 400W Modular Power Supplies

Page 35: Functional Test Automotive Seminar in Mexico

U8972A – VALUE PROPOSITION

Value 1

Throughput

Improvement

Value 2

Floorspace

reduction

Value 3

New Applications

Ease of use

Lower maintenance cost

Page 36: Functional Test Automotive Seminar in Mexico

U8972A Value Proposition 1 –

Throughput Improvement via ≥ 2-DUT test operation (Speed is KING!)

Description E8786B (Venturi S2)

U8972A (Venturi S3)

%Savings

Test

Time/DUT

(s)

59s 39s

Est. Annual

output

per system

285K 431K

System

Price

$140K $179K

DUT

cost/system/

year

$0.49 $0.41 15.4%

DUT DUT

In-sequence test

TS-5400 (Venturi S2)

Note:

Assumption made for Annual output calculation:

1 system is running at 80% capacity for 12 months with 2 shifts (8hr/shift)

DUT

DUT

U8972A (Venturi S3)

DUT

DUT

Page 37: Functional Test Automotive Seminar in Mexico

Value Proposition 2 –

Floor space & Operator reduction of 50% vs. Venturi S2 via 2-DUT parallel

test support

Note:

Operator wages & floor space cost vary from location to location

Assumption made for Annual output calculation:

1 system is running at 80% capacity for 12 months with 2 shifts (8hr/shift)

2-DUT test

DUT

E8786B (Venturi 2)

DUT

DUT

U8972A

(Venturi

S3)

DUT

E8786B

(Venturi S2) DESCRIPTION 2x

E8786B

1x

U8972A

%

Savings

Test time/DUT (s) 29.5s 39s

DUT vol. output/year

(K units)

570K 431K

Total system price

(US$K)

$280K $179K

System cost/DUT/year

(US$)

$0.49 $0.41

Operator wages/DUT/year

(US$)

$0.04 $0.03

Total Cost/DUT/year (US$) $0.53 $0.44 17%

Page 38: Functional Test Automotive Seminar in Mexico

Conventional Method

DMM + Pin Matrix

Sequential measurement

Path needs to be

switched

New Method

M9216A HV-DAQ

Parallel measurement

Does NOT require an

external switch matrix

or multiplexer

DMM 3ms

P01

P02

P03

P04

P05

P06

P07

P08

P09

P10

P11

P12

P13

P14

P15

P16

DUT

Total Test time: 24ms*

Output Pins 6ms

9ms

12ms

15ms

18ms

21ms

24ms

M9216A

3ms P01

P02

P03

P04

P05

P06

P07

P08

P09

P10

P11

P12

P13

P14

P15

P16

DUT

Total Test time: 3ms*

Speed Improvement = 87.5%

Output Pins 3ms

3ms

3ms

3ms

3ms

3ms

3ms

Parallel Test Method Enabler for Automotive

Page 39: Functional Test Automotive Seminar in Mexico

• Used for stimulus and

measurement signal

routing.

• 32x4 and 64x4 pin matrix

for selection.

• Up to 24 instrument matrix.

• Up to 4 analog bus lines.

Agilent Switch Unit for Automotive

Pin Matrix Cards Load Cards

• User for DUT load simulation.

• 8 to 48 channels per card.

• Up to 30A current with fly-back

protection.

• Supports pull-up, pull-down, and

bridge load connection.

• Supports inductive/resistive

loads – single or multiple.

Stimulus and Measurement

Instrumentations

DUT

Load Simulations

Page 40: Functional Test Automotive Seminar in Mexico

E6198B Switch/Load Unit (SLU) Overview

Page 40

MSD-FMT / SLU SHP & PRC/PC checkpoint

Agilent Restricted

09 June 2010

Standalone System Integrated

New E6198B SLU

• Multi-channel support

• Improved reliability and safety

Lower risk of backplane failure

Utilization of fuses

• Introducing two versions, available for standalone orders

SLU Improvements

• Improvements to back plane for reliability and safety • Break out panel for easy access to SLU settings • Improved switching speed for better throughput

Introducing the NEW Standalone SLU

• Bench top usable SLU • External access for cables with protective cover • SLU setting selection at rear panel

Page 41: Functional Test Automotive Seminar in Mexico

E6198B Switch/Load Unit Summary

Page 45

MSD-FMT / SLU SHP & PRC/PC checkpoint

Agilent Restricted

09 June 2010

• 150W 5v, 150W 12v and 25W for -12v power supply. Support full switching capability

• Power bus current rating increased from 22A to 30A.

• SLU dimension maintained. Compatible with existing system layout

• Backward compatible with all cards supported by existing SLU

• Fuse protection prevent over current from power supply

• Easy communication connection access at front panel via USB

• Status Indicators

• Qualified as standalone product

Page 42: Functional Test Automotive Seminar in Mexico

E6198B Switch/Load Unit Summary

Page 46

MSD-FMT / SLU SHP & PRC/PC checkpoint

Agilent Restricted

09 June 2010

New Load and Switch Cards

New Switch Cards

E8782A 64-Channel Matrix with Instrumentation Matrix

E8783A 64-Channel Matrix without Instrumentation Matrix

New Load Cards

N9377A 16-Channel Dual Load Card (7.5A)

N9378A 24-Channel Quad Load Card (2.0A)

N9379A 48-Channel Dual Load Card (2.0A)

E6177B 24-Channel Load Card (2.0A) with current sense will replace the older E6177A model without the I-sense capability

Load Cards being Replaced

Page 43: Functional Test Automotive Seminar in Mexico

Matrix & Load Cards from Agilent

Pin matrix & load cards

E6198B

SLU

Pin Matrix Cards E8782A-FG (24-ch inst, 40-ch matrix)

E8783A-FG (64-ch matrix)

Load Cards E6175A-FG (8-ch, 7.5A, inductive load)

E6176A-FG (16-ch, 7.5A common load)

E6177A-FG (24-ch, 3A, low current load)

E6178B-FG (8-ch, 30A, hi-current load)

N9378A-FG (24-ch, 1A, lo-current, quad load)

N9379A-FG (48-ch, 1A, lo-current, quad load)

U7177A-FG (24-ch, 7.5A, common load, I-sense)

U7178A-FG (8-ch, 40A, hi-current load)

U7179A-FG (16-ch, 15A, hi-current load)

Page 44: Functional Test Automotive Seminar in Mexico

Agenda

1. Automotive Market Overview

2. Automotive Electronics Functional Test

4. Agilent Functional Test Solutions

6. Question & Answer (Q&A) Session

3. Functional Test Challenges

5. HEV/EV – Functional test & Solutions

Page 45: Functional Test Automotive Seminar in Mexico

Market Dynamics

Battery Management System

In vehicle – Drive system Outside vehicle - Infrastructure

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

2010 2011 2012 2013 2014 2015

Electric vs Internal Combustion Vehicle

Light Duty Vehicles

Electric Vehicles

Source – Pike Market Research

• Electric vehicle only constitute 2% of

overall market opportunity today

• Infrastructure will be needed in order to

make EV successful

• Huge potential growth opportunity for

companies develop batteries, motors, on

board chargers and EV components that

enhance performance and safety

Page 46: Functional Test Automotive Seminar in Mexico

Block / Module

EV /HEV modules

Cell Pack

Battery

Inverters

Inverter Converter Controller

Converters BMS

Acronym

BMS – Battery Management System

Page 47: Functional Test Automotive Seminar in Mexico

Agilent focus in HEV, EV & PHEV

Outside the car

• Home charging station

• Public charging station

Inside the car

• Battery Management System

• DC to DC converters

• DC to AC inverters

Agilent’s focus

Page 48: Functional Test Automotive Seminar in Mexico

EV & HEV customer’s challenges

High system

uptime -

Designed for

manufacturing

and easy to

troubleshoot

Acronym

ASP – Average Selling Price

Floor space

– Solution that

optimize floor

space usage

Test Speeds

– Long test

time 3 – 12

mins

depending on

the test

requirements

Product

certification

– CE and

safety

certified with

extraordinary

safety

features

System price

– Optimized

power matrix

and power

supply for

better cost

Page 49: Functional Test Automotive Seminar in Mexico

DUT

Fixture

DUT

Cooling

system

Customer’s

None

Standard

Functional

test system

650mm

Agilent EV, HEV and PHEV proposal

Power Supply and

Electronic Load

High power

Switch

3 Phase motor

and added

instruments

650mm 650mm 650mm

1950mm

High Powered

Power supply and Eload

Power

Matrix

650mm 650mm

Agilent

Standard Platform

Value propositions

1. Leverage Agilent Standard

platform

2. Compact power switching

• Less floor space required

• Easy maintenance

3. High safety features

Page 50: Functional Test Automotive Seminar in Mexico

Cell Balancing – Background information

• Balancing compensates for any underperforming cells in a

battery.

• During charge, a degraded cell with a diminished capacity will

become fully charged sooner so it will be subject to

overcharging until the rest of the cells reach their full charge.

• During discharging, the weakest cell will have the greatest

depth of discharge causing premature failure.

• Cell balancing extends the battery pack’s life by compensating

for weaker cells by equalizing the charge state on each cell.

Agilent application specific value proposition (example)

Page 51: Functional Test Automotive Seminar in Mexico

Cell Balancing Challenges

• Could be a long process. In some cases, takes nearly 1 hour.

• If individual cells are balanced by discharging through resistors --

• Discharging circuit cost and complexity is low, but …

• Time is long: All cells must be discharged to lowest cell voltage.

• Limited control: Fixed R means one discharge rate; Using multiple

Rs to select discharge rate raises cost and complexity.

• Active balancing can significantly speed up balancing process

from 2x to 10x by charging some cells and discharging

others to balance to the mid-voltage point.

Page 52: Functional Test Automotive Seminar in Mexico

Active balancing with Agilent N6783A-BAT

Overview of process

Process:

• Measure voltage of each cell

• Calculate mid point (Vmid)

• Program cells above Vmid to

discharge down to Vmid

• Program cells below Vmid to

charge up to Vmid

• Cuts balancing time in half,

at a minimum

Options:

• Further decrease balancing time

with higher charge/discharge rates

• Maintain cell safety with pulsed or

variable rates

• Since charge/discharge function is

PC controlled one can develop

more advanced algorithms to

optimize speed and complexity

Some cells charging, some discharging

Cell 1

Cell 2

Cell 3

Cell N

N6783A-BAT

Charger-Discharger

#1 = Charging

N6783A-BAT

Charger-Discharger

# N = Discharging

N6783A-BAT

Charger-Discharger

# 3 = Charging

N6783A-BAT

Charger-Discharger

# 2 = Discharging

Page 53: Functional Test Automotive Seminar in Mexico

Agenda

58

1. Automotive Market Overview

2. Automotive Electronics Functional Test

4. Agilent Functional Test Solutions

6. Question & Answer (Q&A) Session

3. Functional Test Challenges

5. HEV/EV – Functional test & Solutions