SP000235288 - Infineon Technologies AG

Data Sheet, V 2.08, September 2008

TLE4997

Programmable Linear Hall Sensor

Sensors

Never stop thinking.

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Edition 2008-09

Published by Infineon Techn ologies AG,

Am Campeon 1-12,

85579 Neubiberg, Germany

Attention pleas e!

The information herein is given to describe certain components and shall not be considered as a guarantee of

characteristics.

Terms of delivery and rights to technical change reserved.

We he reby disclai m any and all warranties, i ncludi ng but not limited to warranties of non-infringement, regardi ng

circuits, descri ptions and charts stated herein.

Information

For further information on technology, delivery terms and conditions and prices please contact your nearest

Infineon Technologies Office (www.infineon.com).

Warnings

Due to technical requirements components may contain dangerous substances. For information on the types in

question please contact your nearest Infineon Technolog ies Office.

Infineon Technologies Compo nent s may on ly be used in life-support devices or systems with the express written

approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure

of that life-support device or system, or to af fect the safety or ef fectiveness o f that device or system. Life support

devices or systems are intended to be implanted in the human body, or to support and/or maintain and sust ain

and/or protect human life. If th ey fail, it is r easonable to assu me th at the health o f the user or other p ersons may

be endangered.

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TLE4997

Revision History: 2008-09 V 2.08

Previous Version: V 2.07, July 2008

Page Subjects (major changes since l ast revision)

12 Table 2: ESD specification (HBM) changed from 2kV to 4kV

general spelling and typing errors

We Listen to Your Comments

Any information within this document that you feel is wrong, unclear or missing at all?

Your feedback will help us to continuously improve the quality of this document.

Please send your proposal (including a reference to this document) to:

sensors@infineon.com

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TLE4997

Data Sheet 4 V 2.08, 2008-09

Table of Contents Page

1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.2 Target Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.3 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

2 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.1 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.3 Principle of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2.4 Further Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2.5 Transfer Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3 Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4 Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5 Electrical and Magnetic Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

6 Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

6.1 Magnetic Field Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

6.2 Gain Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6.3 Offset Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6.4 DSP Input Low Pass Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.5 DAC Input Interpolation Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

6.6 Clamping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

7 Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

7.1 Voltages Outside the Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

7.2 Open Circuit of Supply Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

7.3 Not Correctable EEPROM Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

8 Temperature Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

8.1 Parameter Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

9 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

9.1 Calibration Data Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

9.2 Programming Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

9.3 Laboratory Evaluation Programmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

10 Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

11 Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

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TLE4997

Data Sheet 5 V 2.08, 2008-09

List of Figures Page

Figure 1 Pin Configuration and Hall Cell Location . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 2 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Figure 3 Examples of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 4 Ratiometry Error Band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 5 Signal Processing Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 6 DSP Input Filter (Magnitude Plot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 7 DAC Input Filter (Magnitude Plot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 8 Clamping Example. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 9 EEPROM Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 10 Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 11 PG-SSO-3-10 (Plastic Green Single Small Outline Package) . . . . . . . 33

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TLE4997

Data Sheet 6 V 2.08, 2008-09

List of Tables Page

Table 1 Pin Definitions and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 2 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Table 3 Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Table 4 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Table 5 Magnetic Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 6 Range Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table 7 Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table 8 Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Table 9 Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Table 10 Low Pass Filter Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Table 11 Low Pass Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Table 12 Clamping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Table 13 Undervoltage and Overvoltage (All values with RL ≥ 10k). . . . . . . . . . 25

Table 14 Open Circuit (OBD Parameters) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Table 15 EEPROM Error Signalling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Table 16 Temperature Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Table 17 Calibration Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Table 18 Programming Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

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Type Marking Ordering Code Package

TLE4997 4997E2 SP000235288 PG-SSO-3-10

TLE4997Programmable Linear Hall Sensor

Data Sheet 7 V 2.08, 2008-09

1 Overview

1.1 Features

• High linear and ratiometric push-pull rail-to-rail output

signal

• 20-bit Digital Signal Processing

• Digital temperature compensation

• 12-bit overall resolution

• Operates from -40°C up to 150°C

• Low drift of output signal over temperature and lifetime

• Programmable parameters stored in EEPROM with single bit error correction:

– magnetic range and magnetic sensitivity (gain)

– zero field voltage (offset)

– bandwidth

– polarity of the output slope

– clamping option

– temperature coefficient for all common magnets

– memory lock

• Re-programmable until memory lock

• Single supply voltage 4.5 - 5.5 V (4 - 7 V in extended range)

• Operation between -200 mT and +200 mT within three ranges

• Slim 3-pin package (Green)

• Reverse polarity and overvoltage protection for all pins

• Output short circuit protection

• On-board diagnostics (wire breakage detection, undervoltage, overvoltage)

• Digital readout of internal temperature and magnetic field values in calibration mode.

• Individual programming and operation of multiple sensors with common power supply

• Two-point calibration of magnetic transfer function

• Precise calibration without iteration steps

• High immunity against mechanical stress, EMC, ESD

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TLE4997

Overview

Data Sheet 8 V 2.08, 2008-09

1.2 Target Applications

• Robust replacement of potentiometers

– No mechanical abrasion

– Resistant to humidity, temperature, pollution and vibration

• Linear and angular position sensing in automotive applications like pedal position,

suspension control, valve or throttle position, headlight levelling and steering angle

• High current sensing for battery management, motor control, and electronic fuse

1.3 Pin Configuration

Figure 1 shows the location of the Hall element in the chip and the distance between the

Hall probe and the surface of the package.

Figure 1 Pin Configuration and Hall Cell Location

Table 1 Pin Definitions and Functions

Pin No. Symbol Function

1VDD Supply voltage / programming interface

2GND Ground

3OUT Output voltage / programming interface

Center of

Hall Probe

AEP03717

0.38

±0.05

2.03±0.1

1.625

±0.1

Hall-Probe

Branded Sid

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TLE4997

General

Data Sheet 9 V 2.08, 2008-09

2 General

2.1 Block Diagram

Figure 2 shows a simplified block diagram.

Figure 2 Block Diagram

2.2 Functional Description

The linear Hall IC TLE4997has been designed specifically to meet the demands of highly

accurate rotation and position detection, as well as for current measurement

applications.

The sensor provides a ratiometric analog output voltage, which is ideally suited to

Analog-to-Digital (A/D) conversion with the supply voltage as a reference.

The IC is produced in BiCMOS technology with high voltage capability and also provides

reverse polarity protection.

Digital signal processing using a 16-bit DSP architecture and digital temperature

compensation guarantees excellent stability over a long period of time.

The minimum overall resolution is 12 bits. Nevertheless, some internal stages work with

resolutions up to 20 bits.

HALL

Bias

DSP

Temp.

Sense

ROM

EEPROM

Interface

enable

OUT

GND

Supply

OBD

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TLE4997

General

Data Sheet 10 V 2.08, 2008-09

2.3 Principle of Operation

• A magnetic flux is measured by a Hall-eff ect cell.

• The output signal from the Hall-effect cell is converted from Analog to Digital signals.

• The chopped Hall-effect cell and continuous-time A to D conversion provide very low

and stable magnetic offset.

• A programmable Low-Pass filter reduces the noise.

• The temperature is measured and A to D converted.

• Temperature compensation is processed digitally using a second order function.

• Digital processing of output voltage is based on zero field and sensitivity value.

• The output voltage range can be clamped by digital limiters.

• The final output value is D to A converted.

• The output voltage is proportional to the supply voltage (ratiometric DAC).

• An On-Board-Diagnostics (OBD) circuit co nnects the output to VDD

or GND in case of errors.

2.4 Further Notes

Product qualification is based on “AEC Q100 Rev. G” (Automotive Electronics Council -

Stress test qualification for integrated circuits).

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TLE4997

General

Data Sheet 11 V 2.08, 2008-09

2.5 Transfer Functions

The examples in Figure 3 show how easily different magnetic field ranges can be

mapped to the output voltage.

• Polarity Mode:

–Unipolar: Only North- or South-oriented magnetic fields are measured.

–Bipolar: Magnetic fields can be measured in both orientations.

The limit points must not be symmetric to the zero field point.

• Inversion: The gain values can be set positive or negative.

Figure 3 Examples of Operation

Note: Due to the ratiometry, voltage drops at the VDD line are imaged in the output

signal.

550

-50

5100

-100

5200

-200

VOUT (V)

VOUT VOUT

B (mT) VOUT (V)

B (mT)

000

Example 1:

- Bipolar Example 2:

- Unipolar

- Big offset

- Output for 3.3 V

Example 3:

- Bipolar

- I nv er ted (neg. gain)

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TLE4997

Maximum Ratings

Data Sheet 12 V 2.08, 2008-09

3 Maximum Ratings

Note: Stresses above those listed under “Absolute Maximum Ratings” may cause

permanent damage to the device. This is a stress rating only and functional

operation of the device at these or any other conditions above those indicated in

the operational sections of this specification is not implied. Furthermore, only

single error cases are assumed. More than one stress/error case may also

damage the device.

Exposure to absolute maximum rating conditions for extended periods may affect

device reliability. During absolute maximum rating overload con ditions (VIN > VDD

or VIN < VSS) the voltage on VDD pins with respect to ground (VSS) must not

exceed the values defined by the absolute maximum ratings.

Table 2 Absolute Maximum Ratings

Parameter Symbol Limit Values Unit Notes

min. max.

Storage temperature TST -40 150 °C

Junction temperature TJ-40 170 °C For 96h 1)

1) For limited time only. Depends on customer temperature lifetime cycles. Please ask for support by Infineon.

Voltage on VDD pins with

respect to ground (VSS)VDD -20 2)

2) max 24 h @ -50°C ≤ Ta < 30°C

max 10 min. @ 30°C ≤ Ta < 80°C

max 30 sec. @ 80°C ≤ Ta < 125°C

max 15 sec. @ 125°C ≤ Ta ≤ 150°C.

20 3)

3) max. 24 h @ TJ < 80°C.

V4) RTHja ≤ 150 K/W

4) Guaranteed by laboratory characterization , tested at ±18V.

Supply current

@ overvoltage IDDov -52 mA

Supply current

@ reverse voltage IDDrev - 75 -mA

Voltage on output pin with

respect to ground (VSS)VOUTov -16 5)

5) Max. 1 ms @ TJ < 30°C; -8.5 V for 100 h @ TJ < 80°C.

16 3) VRTHja ≤ 150 K/W

Vout may be > VDD

Magnetic field BMAX -unlimited T

ESD protection VESD -4.0 kV According HBM

JESD22-A114-B 6)

6) 100 pF and 1.5 kΩ

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TLE4997

Operating Range

Data Sheet 13 V 2.08, 2008-09

4 Operating Range

The following operating conditions must not be exceeded in order to ensure correct

operation of the TLE4997. All parameters specified in the following sections of this

document refer to these operating conditions, unless other wise indicated.

Table 3 Operating Range

Parameter Symbol Limit Values Unit Notes

min. max.

Supply voltag e VDD 4.5 5.5 V

4 7 V Extended range 1)

1) For reduced output accuracy.

Output current IOUT -1 1mA 2)

2) For VOUT within the range of 5% ... 95% of VDD.

Load resistance RL10

10 -

-kΩPull-down to GND

Pull-up to VDD

Load capacitance CL0210 nF

Junction temperature 3)

3) RTHja ≤ 150 K/W.

TJ-40 125

150 °C For 5000h

For 1000h4) 5)

4) For reduced magnetic accuracy.

5) Not additive.

Note: Keeping signal levels within the limits specified in this table ensures operation

without overload conditions.

Useful lifetime tLive -16 years

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TLE4997

Electrical and Magnetic Parameters

Data Sheet 14 V 2.08, 2008-09

5 Electrical and Magnetic Parameters

Table 4 Electrical Characteristics

Parameter Symbol Limit Values Unit Notes

min. typ. max.

Output voltage range VOUT 5

6-95

94 % of

VDD

For TA ≤ 120°C

For TA > 120°C

Supply current IDD 37.5 10 mA 1)

1) Also in extended VDD range. For VOUT within the range of 5%... 95% of VDD, IOUT= 0mA.

Output current @ OUT

shorted to supply lines IOUTsh -30 -30 mA For operating supply

voltage range only

Zero field voltage VZERO -100 -100 %Of VDD 2)

2) Programmable in steps of 1.22 mV ( @ VDD = 5V ).

Zero field voltage drift

∆

VZERO -10 -10 mV In lifetime 3)

3) For Sensitivity S ≤ 25 mV/mT. For higher sensitivities the magnetic offset drift is dominant. This means that for

the precalibrated (typical) 60mV/mT sensitivity the typical output drift might be given due to the allowed

magnetic offset toleren c e up to ±0.4mT x 60 mV/mT = ±24 mV.

-10 -10 mV Error band ov. temp.4)

Ratiometry error ERAT -0.25 -+0.25 %Of VDD4)5)

4) For 4.5 V≤VDD≤5.5 V and within nominal VOUT range; see “Ratiometry” on Page 15 for details on ERAT.

5) For the maximum error in the extended voltage range, see “Ratiometry” on Page 15.

Thermal resistance RthJA - - 219 K/W Junction to air

RthJC - - 47 K/W Junction to case

Power on time tPon - - 1

10 ms

∆

VOUT ≤ ± 5% of VDD

∆

VOUT ≤ ± 1% of VDD

Power On Reset level VDDpon 2 - 4 V

Output DAC quantization

∆

VOUT 1.22 mV @ VDD = 5 V

Output DAC resolution -12 bit

Output DAC bandwidth fDAC -3.2 -kHz Interpolation filter 6)

6) More information, see “DAC Input Interpolation Filter” on Page 22.

Output noise Vnoise - - 4.68 mVpp 5% exceeded 7)8)

7) 100 mT range, sensitivity 60 mV/mT, LP-filter 244 Hz, 160 Hz extern al RC low pass filter as application circui t.

8) ’5% exceeded’ means that 5 of 100 continuously measured VOUT samples are out of limit.

Differential non-linearity DNL -1 - 1 LSB Of output DAC

Signal delay tDS - - 250 µs @ 100 Hz 9)

9) A sinusoidal magnetic field is applied, VOUT shows amplitude of 20% of VDD, no LP filter is selected.

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TLE4997

Electrical and Magnetic Parameters

Data Sheet 15 V 2.08, 2008-09

Ratiometry

The linear Hall sensor works like a potentiometer. The output voltage is proportional to

the supply voltage. The division factor depends on the magnetic field strength. This

behavior is called “ratiometric”’.

The supply voltage VDD should be used as the reference for the A/D Converter of the

microcontroller. In this case, variations of VDD are compensated.

The ratiometry error is defined as follows:

The ratiometry error band displays as a “Butterfly Curve”.

Figure 4 Ratiometry Error Band

Note: Take care of possible voltage drops on the VDD and VOUT line degrading the

result. Ideally, both values are acquired and their ratio is calculated to gain the

highest accuracy. This method should be used especially during calibration.

ERAT VOUT VDD

()

VDD

-------------------------------VOUT 5V()

---------------------------

–







= 100× %

RAT

4567

0.25

0.5

0.75

-0.25

-0.5

-0.75

-1

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TLE4997

Electrical and Magnetic Parameters

Data Sheet 16 V 2.08, 2008-09

Calculation of the Junction Temperature

The total power dissipation PTOT of the chip increases its temperature above the ambient

temperature.

The power multiplied with the total thermal resista nce RthJA (Junction to Ambient) leads

to the final junction temperature. RthJA is the sum of the addition of the values of the two

components Junction to Case and Case to Ambient.

RthJA = RthJC + RthCA

TJ = TA +

∆

T = RthJA x PTOT = RthJA x ( VDD x IDD + VOUT x IOUT ) IDD , IOUT > 0, if direction is into IC

Example (assuming no noticeable load on Vout):

–VDD = 5 V

–IDD = 10 mA

–

∆

T = 219 [K/W] x (5 [V] x 0.01 [A] + 0 [VA]) = 11 K

For moulded sensors, the calculation with RthJC is more adequate.

Magnetic Parameters

Table 5 Magnetic Characteristics

Parameter Symbol Limit Values Unit Notes

min. typ. max.

Sensitivity S± 12.5 -± 300 mV/mT 1) 2)

1) Programmable in steps of 0.024%.

2) @ VDD = 5 V and TJ = 25°C

Magnetic field range MFR ± 50 ± 1003)

3) This range is also used for temperature and offset pre-calibration of the IC.

± 200 mT Programmable 4)

4) Depending on the Offset and Gain settings, the output may saturate at lower fields.

Integral nonlinearity INL -15 -15 mV = ± 0.3% of VDD5)

5) INL = Vout - Vout,lse with Vout,lse = least square error fit of Vout.

Valid in the range (5% of VDD) < VOUT < (95% of VDD) for TJ ≤ 120°C

and (6% of VDD) < VOUT < (94% of VDD) for 120°C < TJ ≤ 150°C

Magnetic offset BOS -400 -400 µT6) 7) 8)

6) In operating temperature range and over lifetime.

7) For Sensitivity S > 25 mV / mT. For lower sensitivities, the zero field voltage drift is dominant.

8) Measured at ± 100 mT range.

Magnetic offset drift ∆BOS - 5 - 5 µT / °C Error band 7)

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TLE4997

Signal Processing

Data Sheet 17 V 2.08, 2008-09

6 Signal Processing

The flow diagram in Figure 5 shows the data processing algorithm.

Figure 5 Signal Processing Flow

Magnetic Field Path

• The analog output signal of the chopped Hall cell is converted in the continuous-time

A/D Converter. The range of the chopped A/D Converter can bet set in several steps

(see Table 6). This assures a suitable level for the A/D Converter.

• After the A/D conversion, a digital low pass filter reduces the bandwidth (Table 10).

• A multiplier amplifies the value according to the gain setting (see Table 8) plus

temperature compensation.

• The offset value is added (see Table 9).

• A limiter reduces the resulting signal to 12 bits and feeds the D/A converter.

Temperature Compensation

(Details are listed in Chapter 8)

• The output signal of the temperature cell is also A/D converted.

• The temperature is normalized by subtraction of the T0 value (zero point of the

quadratic function).

• The linear path is multiplied with the TC1 value.

S tor ed in

EEPROM

Memory

-T

Temperature

Compensation

Hall

Sensor

Temperature

Sensor

Limiter

(Clamp)

out

Range LP

DAC

Offset

Gain

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TLE4997

Signal Processing

Data Sheet 18 V 2.08, 2008-09

• In the quadratic path, the difference temperature is squared and multiplied with the

TC2 value.

• Both path outputs are added together to the gain value from the EEPROM.

6.1 Magnetic Field Ranges

The working range of the magnetic field defines the input range of the A/D Converter. It

is always symmetric to the zero field point . Any two points in the magnetic range can be

selected to be the end points of the output curve. The output voltage represents the

range between the two points.

In the case of fields higher than the range values, the output signal may be distorted.

The range must be set before the calibration of offset and gain.

Table 6 Range Setting

Range Range in mT Parameter R

Low ± 50 3

Mid ± 100 1

High ± 200 0

Table 7 Range

Parameter Symbol Limit Values Unit Notes

min. max.

1) Ranges do not have a guaranteed absol ute accuracy. The temperature pre-calibration is performed in the mid

range (100 mT).

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Signal Processing

Data Sheet 19 V 2.08, 2008-09

6.2 Gain Setting

The sensitivity is defined by the range and the gain setting. The output of the A/D

Converter is multiplied with the gain value.

The gain value can be calculated by

6.3 Offset Setting

The offset voltage corresponds to an output voltage with zero field at the sensor.

The offset value can be calculated by:

Table 8Gain

Parameter Symbol Limit Values Unit Notes

min. max.

Gain range Gain - 4.0 3.9998 -1)2)

1) For gain values between - 0.5 and + 0.5, the numeri c accuracy decreases.

To obtain a flatter output curve, it is recommended to select a higher range setting.

2) A gain value of +1.0 corresponds to a typical 40 mV/mT sensitivity (100 mT range, not guaranteed). Infineon

pre-calibrates the samples to 60mV/mT (100mT range) in the final test, but does not guarantee the accuracy

of this calibration. It is crucial to do a final calibration of each IC within the application using the Gain/VOS value.

Gain quantization steps ∆Gain 244.14 ppm Corresponds to 1/4096

Table 9 Offset

Parameter Symbol Limit Values Unit Notes

min. max.

Offset range VOS -400 399 % VDD 1)

1) Infineon pre-calibrates the samples at zero field to 50% of VDD (100mT range) in the final test, but does not

guarantee the accu racy of this calibration. It is crucial to do a final calibration of each IC wi thin the application

using the Gain/VOS value.

Offset quantization

steps ∆VOS 1.22 mV @ VDD = 5 V

generally VDD / 4095

Gain G 16384–()

4096

------------------------------

VOS OS 16384–()

4096

--------------------------------- VDD

×=

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Signal Processing

Data Sheet 20 V 2.08, 2008-09

6.4 DSP Input Low Pass Filter

A digital Low Pass Filter is placed between the Hall A/D Converter and the DSP to

reduce the noise level. The Low Pass filter has a constant DC amplification of 0 dB (this

is exactly a gain of 1), which means that its setting has no influence on the internal Hall

A/D Converter value.

The bandwidth can be set in 8 steps.

Table 10 Low Pass Filter Setting

Note: In Low Pass filter setting 7 (filter off), the output noise increases. Because of

higher DSP load, the current consumption also rises slightly.

Parameter LP Cutoff frequency in Hz (at 3dB attenuation)1)

1) As this is a digital filter running with an RC-based oscillator, the cutoff frequency may vary within ±25%.

078

1244

2421

3615

4826

51060

61320

7off 2)

2) The output low pass-interpolation filter behavior remains as main component in the signal path.

Table 11 Low Pass Filter

Parameter Symbol Limit Values Unit Notes

min. max.

Corner frequency

variation ∆ f - 25 + 25 %

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TLE4997

Signal Processing

Data Sheet 21 V 2.08, 2008-09

Figure 6 shows the characteristic of the filter as a magnitude plot (the highest setting is

marked). The “off” position would be a flat 0 dB line. In this case, the output decimation

filter limits the bandwidth of the sensor. The update rate after the Low Pass filter is

16 kHz.

Figure 6 DSP Input Filter (Magnitude Plot)

-6

-5

-4

-3

-2

-1

M agni tude ( dB)

Fr equency ( Hz)

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Signal Processing

Data Sheet 22 V 2.08, 2008-09

6.5 DAC Input Interpolation Filter

An interpolation filter is placed between the DSP and the output DAC. It cannot be

switched off. This filter limits the frequency behavior of the complete system if the DSP

input filter is disabled. The update rate after the interpolation filter is 256 kHz.

Figure 7 DAC Input Filter (Magnitude Plot)

Note: As this is a digital filter running with an RC-based oscillator, the cutoff frequency

may vary within ±25%.

-6

-5

-4

-3

-2

-1

M agni tude ( dB)

Fr equency ( Hz) 10

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TLE4997

Signal Processing

Data Sheet 23 V 2.08, 2008-09

6.6 Clamping

The clamping function is useful for splitting the output voltage into the operating range

and error ranges. If the magnetic field is outside the selected measurement range, the

output voltage Vout is limited to the clamping values.

The clamping values are calculated by:

Clamping low voltage:

Clamping high voltage:

Note: For an exact setup, the register value may be re-adjus ted due to the actual output

voltage in the clamping condition. The output voltage range itself has electrical

limits. See the Electrical Characteristics of Vout.

Table 12 Clamping

Parameter Symbol Limit Values Unit Notes

min. max.

Clamping voltage low VCLL 099.98 % VDD 1)

1) If clamping is set, it must be within the allowed output voltage range to be effective.

Clamping voltage high VCLH 099.98 % VDD 1)

Clamping quantization

steps

∆

VCLQ 1.22 mV @ VDD = 5 V

Clamping voltage drift

∆

VCL -15 15 mV in lifetime2)

2) Valid in the range (5% of VDD) < VOUT < (95% of VDD) for TJ ≤ 120°C

and (6% of VDD) < VOUT < (94% of VDD) for 120°C < TJ ≤ 150°C

-15 15 over temperature2)

VCLL CL

4096

------------VDD

×=

VCLH CH

4096

------------VDD

×=

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TLE4997

Signal Processing

Data Sheet 24 V 2.08, 2008-09

Figure 8 shows an example in which the magnetic field range between Bmin and Bmax

is mapped to voltages between 0.8 V and 4.2 V.

If it is not necessary to signal errors, the maximum output voltage range between 0.3 V

and 4.7 V can be used.

Figure 8 Clamping Example

Note: The high value must be above the low value.

If VCLL is set to a higher value than VCLH, the VCLH value is dominating. This would

lead to a constant output voltage independent of the magnetic field strength.

min

B (mT)

max

out

(V)

Error rang e

Operating range

CLH

CLL

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TLE4997

Error Detection

Data Sheet 25 V 2.08, 2008-09

7 Error Detection

Different error ca ses can b e detected by the On-Board-Diagnostics (OBD) and reported

to the microcontroller. The OBD is useful only when the clamping function is enabled. It

is important to set the clamping threshold values inside the error voltage values shown

in Table 13 and Table 14 to ensure that it is possible to distinguish between correct

output voltages and error signals.

7.1 Voltages Outside the Operating Range

The output signals error conditions, if VDD lies

• inside the ratings specified in Table 2 "Absolute Maximum Ratings" on Page 12

• outside the range specified in Table 3 "Operating Range" on Page 13.

7.2 Open Circuit of Supply Lines

In the case of interrupted supply lines, the data acquisition device can alert the user. If

two sensors are placed in parallel, the output of the remaining working sensor may be

still used for an emergency operation.

Table 13 Undervoltage and Overvoltage (All va lues with RL ≥ 10k)

Parameter Symbol Limit Values Unit Notes

min. max.

Undervoltage threshold VDDuv 3 4 V

Overvoltage threshold VDDov 78.3 V

Output voltage

@ undervoltage VOUTuv 0.95 x VDD - V 3V ≤ VDD ≤ VDDuv

Output voltage

@ overvoltage VOUTov 0.97 x VDD - V VDDov < VDD ≤ 16 V

Supply current 1)

1) For overvoltage and reverse voltage, see Table 2 "Absolute Maximum Ratings" on Page 12.

IDDuv -10 mA @ undervoltage

Table 14 Open Circuit (OBD Parameters) 1)

1) With VDD = 5 V and RL ≥ 10 kΩ pull-down or RL ≥ 20 kΩ pull-up.

Parameter Symbol Limit Values Unit Notes

min. max.

Output voltage

@ open VDD line VOUT 00.18

0.2 V TJ≤120°C

120°C < TJ ≤ 150°C

Output voltage

@ open GND line VOUT 4.82

4.8 5 V TJ≤120°C

120°C < TJ ≤ 150°C

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Error Detection

Data Sheet 26 V 2.08, 2008-09

7.3 Not Correctable EEPROM Errors

The parity method is able to correct one single bit in one EEPROM line. One other single

bit error in another line can also be detected. As this situation is not correctable, this

status is signalled at the output pin by clamping the output value to VDD.

Table 15 EEPROM Error Signalling

Parameter Symbol Limit Values Unit Notes

min. max.

Output voltage @

EEPROM error VOUT 0.97 x VDD VDD V

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TLE4997

Temperature Compensation

Data Sheet 27 V 2.08, 2008-09

8 Temperature Compensation

The magnetic field strength of a magnet depends on the temperature. This material

constant is specific to different magnet types. Therefore, the TLE4997 offers a second

order temperature compensation polynomial, by which the Hall signal output is multiplied

in the DSP. There are three parameters for the compensation:

• Reference temperature T0

• A linear part (1st order) TC1

• A quadratic part (2nd order) TC2

The following formula describes the sensitivity dependent on the temperature in relation

to the sensitivity at the reference temperature T0:

For more information, see also the signal processing flow in Figure 5.

The full temperature compensation of the complete system is done in two steps:

1. Pre-calibration in the Infineon final test.

The parameters TC1, TC2, T0 are set to maximally flat temperature characteristics

regarding the Hall probe and internal analog processing parts.

2. Overall System calibration.

The typical coefficients TC1, TC2, T0 of the magnetic circuitr y are programmed. This

can be done deterministically, as the algorithm of the DSP is fully reproducible. The

final settings of the TC1, TC2, T0 values are relative to the pre-calibrated values.

Table 16 Temperature Compensation

Parameter Symbol Limit Values Unit Notes

min. max.

1st order coefficient TC1TC1-1000 2500 ppm/ °C 1)

1) Full adjustable range: -2441 to +5355 ppm/°C, can be only used after confirmation by Infineon

Quantization steps of TC1

∆

TC115.26 ppm/ °C

2nd order coefficient TC2TC2- 4 4 ppm/ °C² 2)

2) Full adjustable range: -15 to +15 ppm/°C², can be only used after confirmation by Infineon

Quantization steps of TC2

∆

TC20.119 ppm/ °C²

Reference temperature T0- 48 64 °C

Quantization steps of T0

∆

T016 °C 3)

3) A quantization step of 1°C is handled by algorithm (See Application Note).

STC T() 1TC1TT

–()×TC2TT

–()

×++=

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TLE4997

Temperature Compensation

Data Sheet 28 V 2.08, 2008-09

8.1 Parameter Calculation

The parameters TC1, TC2 and T0 may be calculated by:

Now the output VOUT for a given field BIN at a specific temperature can be roughly

calculated by:

BFSR is the full range magnetic field. It is dependent on the range setting (e.g 100 mT).

So is the nominal sensitivity of the Hall probe times the Gain factor set in the EEPROM.

STC is the temperature-dependent sensitivity factor calculated by the DSP.

STCHall is the temperature behavior of t he Hall probe.

The pre-calibration at Infineon is performed such that the following condition is met:

Within the application, an additional factor BIN(T) / BIN(T0) will be given due to the

magnetic system. STC needs now to be modified to STCnew so that the following condition

is satisfied:

Therefore, the new sensitivity parameters STCnew can be calculated from the

pre-calibrated setup STC using the relation:

TC1TL 160–

65536

---------------------- 1000000×=

TC2TQ 128–

8388608

----------------------- 1000000×=

T016TR 48–=

VOUT BIN

BFSR

-------------STC

×STCHall

×SoVDD

××







VOS

STC TJT0

–()STCHall TJ

()×1≈

BIN T()

BIN T0

()

-------------------- STCnew T() STCHall T()×× STC T() STCHall T()×1≈≈

BIN T()

BIN T0

()

-------------------- STCnew T()×STC T()≈

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TLE4997

Calibration

Data Sheet 29 V 2.08, 2008-09

9Calibration

A special hardware interface to an external computing system and measurement

equipment is required for calibration of the sensor. All calibration and setup bits can be

written into a random access memory (RAM). This allows the EEPROM to remain

untouched during the entire calibration process. Therefore, this temporary setup (using

the RAM only) does not stress the EEPROM— and even allows a pre-verification1) of the

setup before programming—as the number of EEPROM programming cycles is limited

to provide a high data endurance.

The digital signal processing is completely deterministic. This allows a two point

calibration in one step without iterations. The two magnetic fields (here described as two

“positions” of an external magnetic circuitry) need to be applied only once. Furthermore,

a complete setup and calibration procedure can be performed requiring only one

EEPROM programming cycle at the end2).

After setting up the temperature coefficients, the ca librated Hall A/D Converter values of

both positions need to be read and the sensor output signals (using a DAC test mode)

need to be acquired for the corresponding end points. Using this data, the signal

processing parameters can be immediately calculated with a program running on the

external computing system.

Note: The calibration and programming process must be performed only at the

start of life of the device.

Note: Depending on the application and external instrumentation setup, the accuracy of

the 2 point calibration can be improved.

1) This feature is not required for a deterministic two-point setup to fulfill the specification.

2) Details and basic algorithms for this step are available on request.

Table 17 Calibration Characteristics

Parameter Symbol Limit Values Unit Notes

min. max.

Temperature of sensor at

2 point calibration and

programming

tCAL 10 30 °C

2 point calibration

accuracy1)

1) Setup and validation performed at start of life.

∆

VCAL1 -10 10 mV Position 1

∆

VCAL2 -10 10 mV Position 2

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TLE4997

Calibration

Data Sheet 30 V 2.08, 2008-09

9.1 Calibration Data Memory

When the MEMLOCK bits are programmed (two redundant bits), the memory contents

are frozen and may no longer be changed. Furthermore, the programming interface is

locked out and the chip remains in Application Mode only. This prevents accidental

programming due to environmental influences.

Figure 9 EEPROM Map

A matrix parity architecture allows the automatic correction of any single bit error. Each

row is protected by a row parity bit. The sum of bits set including this bit must be an odd

number (ODD PARITY). Each column is additionally protected by a column parity bit.

The sum of all the bits in the even positions (0, 2, etc.) of all lines must be an even

number (EVEN PARITY); the sum of all the bits in the odd positions (1,3, etc.) must be

an odd number (ODD PARITY). This mechanism o f different parity calculations protects

against many block errors (such as erasing a full line or even the entire EEPROM).

When modifying the application bits (such as Gain, Offset, TC, etc.) the parity bits must

be updated. For the column bits, the pre-calibration area must be also read out and

considered for correct parity generation.

Note: A specific programming algorithm must be followed to ensure the data retention.

A separate detailed programming specification is available on request.

User - Calibr at ion Bit s

Pr e - Ca libration Bit s

Column Parity Bits

RowA Par ity Bits

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TLE4997

Calibration

Data Sheet 31 V 2.08, 2008-09

9.2 Programming Interface

The supply pin and the output pin are used as two-wire interface to transmit the

EEPROM data to and from the sensor.

This allows

• communication with high data reliability

• bus-type connection of several sensors

In many applications, two sensors are used to measure the same parameter. This

redundancy allows the operation to continue in an emergency mode. If both sensors use

the same power supply lines, they can be programmed together in parallel.

The data transfer protocol and programming is described in a separate document

(TLE4997 Programming Guide).

9.3 Laboratory Evaluation Programmer

For the programming of evaluation samples and QA (quality assurance) samples a

programming equipment is available on request.

Table 18 Programming Characteristics

Parameter Symbol Limit Values Unit Notes

min. max.

Number of EEPROM

programming cycles NPRG -10 Cycles

1) 1 cycle is the simultaneous change of ≥ 1 bit.

Programming allowed

only at start of lifetime

Ambient temperature at

programming TPRG 10 30 °C

Programming time tPRG 100 -ms For complete memory 2)

2) Depending on clock frequency at VDD, write pulse 10ms ±1%, erase pulse 80ms ±1%.

Calibration memory -135 Bit All active EEPROM bits

Error correction -25 Bit All parity EEPROM bits

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TLE4997

Application Circuit

Data Sheet 32 V 2.08, 2008-09

10 Application Circuit

Figure 10 shows the connection of multiple sensors to a microcontroller.

Figure 10 Application Circuit

Note: For calibration and programming, the interface must be connected directly to the

output pin.

The given application circuit must be regarded as only an example. It needs to be

adapted according to the requirements of the specific application.

optional

Voltage Tracker

e.g.

TLE4250

Ref

ADC

ref

ADC

in1

ADC

in2

ADC

GND

47nF 10k

100 nF10k100 nF47nF

47nF 10k

100 nF10k100 nF47nF

µC

TLE

4997

out

GND

TLE

4997

out

GND

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TLE4997

Package Outlines

Data Sheet 33 V 2.08, 2008-09

11 Package Outlines

Figure 11 PG-SSO-3-10 (Plastic Green Single Small Outline Package)

1) No solder function area

Molded body dimensions do not unclude plastic or metal protrusion of 0.15 max per side

±0.3

12.7

±0.4

6.35

12.7±1

Total tolerance at 19 pitches ±1

±0.3

±0.5

-0.50

+0.75

33 MAX.

(Useable

Length)

(10)

±0.5

-1

-0.15

0.25

±0.1

0.39

Tape

Adhesive

Tape

(0.25)

±0.2 1)

0.1 MAX.

0.5

±0.05

±0.1

0.42 3x

1.5

±0.05

4.06

4.05

±0.05

2 x 1.27 = 2.54

±0.05

1.5

0.36 ±0.05

0.82±0.05

P-PG-SSO-3-10-PO V02

45˚

5˚

123

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www.infineon.com

Published by Infineon Technologies AG

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