TLE4998S4HALA1 - INFINEON TECHNOLOGIES AG

Data Sheet, V 1.0, July 2008

TLE4998S3

TLE4998S4

Programmable Linear Hall Sensor

Sensors

Never stop thinking.

Edition 2008-07

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

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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.

Template: mc_a5_ds_tmplt.fm / 4 / 2004-09-15

TLE4998S

Revision History: 2008-07 V 1.0

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TLE4998S
  
Data Sheet 4 V 1.0, 2008-07 
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
2 Target Applications  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  7
3 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  7
General  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
1 Block Diagram  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
3 Principle of Operation  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  10
4 Transfer Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  11
Maximum Ratings  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  12
Operating Range  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  13
Electrical, Thermal, and Magnetic Parameters . . . . . . . . . . . . . . . . . . .  14
Calculation of the Junction Temperature  . . . . . . . . . . . . . . . . . . . . . .  16
Magnetic Parameters  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  16
Signal Processing  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  18
Magnetic Field Path  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  18
Temperature Compensation  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  18
1 Magnetic Field Ranges  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  19
2 Gain Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  20
3 Offset Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  20
4 DSP Input Low-Pass Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
5 Clamping  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
1 Voltages Outside the Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
2 EEPROM Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
Temperature Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
1 Parameter Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
Calibration  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  28
1 Calibration Data Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  29
2 Programming Interface  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  30
3 Data Transfer Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  30
4 Programming of Sensors with Common Supply Lines   . . . . . . . . . . . . . . .  30
Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  31
TLE4998S3 Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  32
TLE4998S4 Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  33
SENT Output Definition (SAE J2716) . . . . . . . . . . . . . . . . . . . . . . . . . . .  34

TLE4998S

Data Sheet 5 V 1.0, 2008-07

13.1 Basic SENT Protocol Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

13.2 Unit Time Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

13.3 Checksum Nibble Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Programmable Linear Hall Sensor

Data Sheet 6 V 1.0, 2008-07

TLE4998S3

TLE4998S4

Type Marking Ordering Code Package

TLE4998S3 4998S3 SP412108 PG-SSO-3-10

TLE4998S4 4998S4 SP412110 PG-SSO-4-1

1 Overview

1.1 Features

• Single Edge Nibble Transmission (SENT) open-drain

output signal (SAE J2716)

• 20-bit Digital Signal Processing (DSP)

• Digital temperature compensation

• 16-bit overall resolution

• Operates within automotive temperature range

• Low drift of output signal over temperature and lifetime

• Programmable parameters stored in EEPROM with

single-bit error correction:

– SENT unit time

– Magnetic range and sensitivity (gain), p olarity of the

output slope

– Offset

– Bandwidth

– Clamping levels

– Customer temperature compensation coefficients

– Memory lock

• Re-programmable until memory lock

• Single supply voltage 4.5 - 5.5 V (4.1 - 16 V in extended range)

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

• Reverse-polarity and overvoltage protection for all pins

• Output short-circuit protection

• On-board diagnostics (overvoltage, EEPROM error, start up)

• Output of internal magnetic field values and temperature

• Programming and operation of multiple sensors with common power supply

• Two-point calibration of magnetic transfer function without iteration steps

• High immunity against mechanical stress, EMC, ESD

TLE4998S

Overview

Data Sheet 7 V 1.0, 2008-07

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 such as pedal position,

suspensi on control, throttle position, headlight levelling, and steering torque sensing

• Sensing of high current for battery management, motor control, and electronic fuses

1.3 Pin Configuration

Figure 1 and Figure 2 show the location of the Hall element in the chip and the distance

between Hall probe and the surface of the package.

Figure 1 TLE4998S3 Pin Configuration and Hall Cell Location

Table 1 TLE4998S3 Pin Definitions and Functions

Pin No. Symbol Function

1VDD Supply voltage / programming interface

2GND Ground

3OUT Output / programming interface

Center of

Hall Probe

AEP0371

0.38

±0.05

2.03±0.1

1.625

±0.1

Hall-Probe

Branded Sid

TLE4998S

Overview

Data Sheet 8 V 1.0, 2008-07

Figure 2 TLE4998S4 Pin Configuration and Hall Cell Location

Table 2 TLE4998S4 Pin Definitions and Functions

Pin No. Symbol Function

1TST Test pin (connection to GND is recommended)

2VDD Supply voltage / programming interface

3GND Ground

4OUT Output / programming interface

AEP0365

PG-SSO-4-1: 0.3

d : Distance chip to branded side of

±0.08

Hall-Probe

Branded Side

2 3 41

Center of

sensitive area

2.67

1.53

BBA 0.2

A0.2

TLE4998S

General

Data Sheet 9 V 1.0, 2008-07

2 General

2.1 Block Diagram

Figure 3 is a simplified block diagram.

Figure 3 Block Diagram (TLE4998S4)

2.2 Functional Description

The linear Hall IC TLE4998S has been designed specifically to meet the requirements

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

applications.

The sensor provides a digital SENT signal based on the SAE J2716 standard, which

consists of a sequence of pulses. Each transmiss ion has a constant number of nibbles

containing the Hall value, the temperature, and status information of the sensor.

The output stage is an open-drain driver pu lling the output pin to low only. Therefore, the

high level needs to be obtained by an external pull-up resistor. This output type has the

advantage that the receiver may use an even lower supply voltage (e.g. 3.3 V). In this

case the pull-up resistor must be connected to the given receiver supply.

The IC is produced in BiCMOS technology with high voltage capability, and it also has

reverse-polarity protection.

spinning

HALL

Bias

DSP

Temp.

Sense

ROM

EEPROM Interface

OUT

VDD

GND

Supply

SENT

TST*)

*) TLE499 8S4 only

TLE4998S

General

Data Sheet 10 V 1.0, 2008-07

Digital signal processing using a 16-bit DSP architecture together with digital

temperature compensation guarantee excellent long-time stability compared to analog

compensation methods.

While the overall resolution is 16 bits, some internal stages work with resolutions up to

20 bits.

2.3 Principle of Operation

• A magnetic flux is measured by a Hall-effect cell

• The output signal from the Hall-effect cell is converted from analog to digital

• The chopped Hall-effect cell and continuous-time A/D conversion ensure a very low

and stable magnetic offset

• A programmable low-pass filter to reduce noise

• The temperature is measured and A/D converted, too

• Temperature compensation is done digitally using a second-order function

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

• The output value range can be clamped by digital limiters

• The final output value is represented by the data nibbles of the SENT protocol

TLE4998S

General

Data Sheet 11 V 1.0, 2008-07

2.4 Transfer Functions

The examples in Figure 4 show how different magnetic field ranges can be mapped to

the desired output value ranges.

• Polarity Mode:

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

points do not necessarily have to be symmetrical around the zero field point

–Unipolar: Only north- or south-oriented magnetic fields are measured

• Inversion: The gain can be set to both positive and negative values

Figure 4 Examples of Operation

4095 /

65535

-50

100

-100

200

-200

OUT

0 0

B (mT) B (m T) B (m T)

000

OUT

4095 /

65535 4095 /

65535

Example 1:

-Bipolar Example 2:

-Unipolar

- Big offset

Example 3:

- Bipolar

- Inv erted ( ne g. gain)

TLE4998S

Maximum Ratings

Data Sheet 12 V 1.0, 2008-07

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.

Exposure to absolute maximum rating conditions for extended periods may affect

device reliability.

Table 3 Absolute Maximum Ratings

Parameter Symbol Limit Values Unit Notes

min. max.

Storage temperature TST - 40 150 °C

Junction temperature TJ- 40 1701)

1) For limited time of 96 h. Depends on customer temperature lifetime cycles. Please ask for support by Infineon

°C

Voltage on VDD pin with

respect to ground VDD -18 18 V2)

2) Higher voltage stress than absolute maximum rating, e.g. 150% in latch-up tests is not applicable. In such

cases, Rseries ≥100 Ω for current limitation is required

Supply current

@ overvoltage VDD max. IDDov -15 mA

Reverse supply current

@ VDD min. IDDrev -1 0mA

Voltage on output pin with

respect to ground VOUT -13)

3) IDD can exceed 10 mA when the voltage on OUT is pulled below -1 V (-5 V at room temperature)

184)

4) VDD = 5 V, ope n drain permanent low, for max. 10 minutes

Magnetic field BMAX -unlimited T

ESD protection VESD -4.0 kV According HBM

JESD22-A114-B 5)

5) 100 pF and 1.5 kΩ

TLE4998S

Operating Range

Data Sheet 13 V 1.0, 2008-07

4 Operating Range

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

operation of the TLE4998S. All parameters specified in the following sections refer to

these operating conditions, unless otherwise indicated.

Table 4 Operating Range

Parameter Symbol Limit Values Unit Notes

min. max.

Supply voltag e VDD 4.5 5.5 V

4.11)

1) For reduced output accuracy

162)

2) For supply voltages > 12 V, a series resistance Rseries ≥ 100 Ω is recommended

VExtended range

Output pull-up voltage3) Vpull-up -18 V

Load resistance3)

3) Required output protocol characteristics depend on these parameters, RL must be according to max. output

current

RL1 - kΩ

Output current3) IOUT 0 5 mA

Load capacitance3) CL1 8 nF

Junction temperature TJ- 40 125

1504)

4) For reduced magnetic accuracy; extended limits are taken for characteristics

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

without overload conditions.

°C For 5000 h

For 1000 h not additive

TLE4998S

Electrical, Thermal, and Magnetic Parameters

Data Sheet 14 V 1.0, 2008-07

5 Electrical, Thermal, and Magnetic Parameters

Table 5 Electrical Characteristics

Parameter Symbol Limit Values Unit Notes

min. typ. max.

SENT transmission time tSENT - - 1 ms 1)

1) Transmission time depends on the data values being sent and on int. RC oscillator freq. variation of +/- 20%

Supply current IDD 3 6 8 mA

Output current @ OUT

shorted to supply lines IOUTsh -95 -mA VOUT = 5 V, max. 10

minutes

Thermal resistance

TLE4998S3 RthJA -219 -K/W Junction to air

RthJC -47 -K/W Junction to case

Thermal resistance

TLE4998S4 RthJA -240 -K/W Junction to air

RthJC -41 -K/W Junction to case

Power-on time2)

2) Response time to set up output data at power on when a constant field is applied. The first value given has a

± 5% error, the second value has a ± 1% error. Measured with 640-Hz low-pass filter

tPon -0.7

15 2

20 ms ≤ ± 5% target out value

≤ ± 1% target out value

Power-on reset level VDDpon -3.6 4 V

Output impedance ZOUT 19 30 44 kΩ3)

3) VDD = 5V, open drain high state, voltage on OUT pin typ. 84% of VDD

Output fall time tfall 2 - 4 µs VOUT 4.5 V to 0.5 V 4)

4) For VDD = 5 V, RL = 2.2 kΩ, CL = 4.7 nF

Output rise time trise -20 -µs VOUT 0.5 V to 4.5 V

4)5)

Output low time tlow - 9 - µs SENT edge generation

Output min. high time tHIGH min -36 -µs SENT “0” nibble

Output max. high time tHIGH max -168 -µs SENT synchron. frame

Output low saturation

voltage VOUTsat -0.3

0.2 0.6

0.4 V IOUTsink = 5 mA

IOUTsink = 2.2 mA

Output noise (rms) OUTnoise - 1 2.5 LSB12 6)

TLE4998S

Electrical, Thermal, and Magnetic Parameters

Data Sheet 15 V 1.0, 2008-07

5) Depends on external RL and CL

6) Range 100 mT, Gain 2.23, internal LP filter 244 Hz, B = 0 mT, T = 25 °C

OUT *)

90% V

10% V

rise t

fall

to V

assumed

low

HIGH

OUTsat

TLE4998S

Electrical, Thermal, and Magnetic Parameters

Data Sheet 16 V 1.0, 2008-07

Calculation of the Junction Temperature

The internal power dissipation PTOT of the sensor increases the chip junction

temperature above the ambient temperature.

The power multiplied by the total thermal resistance RthJA (Junction to Ambient) added

to TA leads to the final junction temperature. RthJA is the sum of the addition 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 load on Vout and TLE4998S4 type):

–VDD = 5 V

–IDD = 8 mA

–

T = 240 [K/W] x (5 [V] x 0.008 [A] + 0 [VA] ) = 9.6 K

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

Magnetic Parameters

Table 6 Magnetic Characteristics

Parameter Symbol Limit Values Unit Notes

min. typ. max.

Sensitivity S1)

1) Defined as ΔOUT / ΔB

± 8.2 -± 245 LSB12/

mT Programmable2)3)

2) Programmable in steps of 0.024%

3) @ VDD = 5 V and TJ = 25 °C

Temperature

coefficient of sensitivity TC -150 0150 ppm/

°C

See Figure 5

Magnetic field range MFR ± 50 ± 1005) ± 200 mT Programmable 6)

Integral nonlinearity INL - 0.1 -0.1 %MFR 7)9)

Magnetic offset BOS - 400 0400 μT8)9)

Magnetic offset drift ΔBOS - 5 - 5 μT / °C Error band9)

Magnetic hysteresis BHYS 0 - 10 μT10)

TLE4998S

Electrical, Thermal, and Magnetic Parameters

Data Sheet 17 V 1.0, 2008-07

Figure 5 Drift of Temperature Coefficient

4) For any 1st and 2nd order polynomial, coefficient within definition in Chapter 8.

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

6) Depending on offset and gain settings, the output may already be saturated at lower fields

7) Gain setup is 1.0

8) In operating temperature range and over lifetime

9) Measured at ± 100 mT range

10) Measured in 100 mT range, Gain = 1, room temperature

ΔS ~

S(T)/S

-1

ΔS0

max. pos.

TC-error

TCmax = ΔS/ΔT

max. neg.

TC-error

TCmin = ΔS/ΔT

Tmin Tmax

TLE4998S

Signal Processing

Data Sheet 18 V 1.0, 2008-07

6 Signal Processing

The signal flow diagram in Figure 6 shows the signal path and data-processing

algorithm.

Figure 6 Signal Processing Flow

Magnetic Field Path

• The analog output signal of the chopped Hall-effect cell is converted to a digital signal

in the continuous-time A/D converter. The range of the chopped A/D co nverter can be

set in several steps (see Table 7). This gives a suitable level for the A/D converter

• After the A/D conversion, a digital low-pass filter reduces the bandwidth (Table 11)

• A multiplier amplifies the value depending on the gain (see Table 9) and temperature

compensation settings

• The offset value is added (see Table 10)

• A limiter reduces the resulting signal to 16 bits (see Chapter 13) and feeds the

Protocol Generation stage

Temperature Compensation

(Details are listed in Chapter 8)

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

Stored in

EEPR OM

Memory

Hall

Sensor

Limiter

(Clamp)

out

Range LP

Offset

Gain

D +

-T0TC1

Temperature

Compensation

TC2

Protocol

Generation

Temperature

Sensor

TLE4998S

Signal Processing

Data Sheet 19 V 1.0, 2008-07

• The temperature is normalized by subtraction of the reference temperature T0 value

(zero point of the quadratic function)

• The linear path is multiplied with the TC1 value

• In the quadratic path, the temperature difference to T0 is squared and multiplied with

the TC2 value

• Both path outputs are added together and multiplied with 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 symmetrical around the zero field point. Any two points in the magnetic field

range can be selected to be the end points of the output value. The output value is

represented within 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 7 Range Setting

Range Range in mT1)

1) Ranges do not have a guara nteed absolute accuracy. The temperature pre-calibration is performed i n the mid

range (100 mT)

Parameter R

Low ± 50 3

Mid ± 100 12)

2) Setting R = 2 is not used, internally changed to R = 1

High ± 200 0

Table 8 Range

Parameter Symbol Limit Values Unit Notes

min. max.

TLE4998S

Signal Processing

Data Sheet 20 V 1.0, 2008-07

6.2 Gain Setting

The overall sensitivity is defined by the range and the gain setting. The output of the ADC

is multiplied with the Gain value.

The Gain value can be calculated by

6.3 Offset Setting

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

The offset value can be calculated by:

Table 9Gain

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 numerical accuracy decreases

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

2) A gain value of +1.0 corresponds to typical 32 LSB12/mT sensitivity (100 mT range, not guaranteed). It is

crucial to do a final calibration of each IC within the application using the Gain/OUTOS value

Gain quantization steps ΔGain 244.14 ppm Corresponds to 1/4096

Table 10 Offset

Parameter Symbol Limit Values Unit Notes

min. max.

Offset range OUTOS -16384 16383 LSB12 1)

1) Infineon pre-calibrate s the samples at zero field to 50% output value (100 mT range), but does not guarantee

the value. Therefore it is crucial to do a final calibration of each IC within the application

Offset quantization

steps ΔOUTOS 1LSB12

Gain G 16384–()

4096

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

OUTOS OS 16384–=

TLE4998S

Signal Processing

Data Sheet 21 V 1.0, 2008-07

6.4 DSP Input Low-Pass Filter

A digital low-pass filter is placed between the Hall A/D converter and the DSP, and can

be used to reduce the noise level. The low-pass filter has a constant DC amplification of

0 dB (Gain of 1), which means that its setting has no influence on the internal Hall ADC

value.

The bandwidth can be set to any of 8 values.

Note: In range 7 (filter off), the output noise increases.

Table 11 Low Pass Filter Setting

Note: Parameter LP Cutoff frequency in Hz (-3dB point)1)

1) As this is a digital filter running with an RC-based oscillator, the cutoff frequency may vary within ±20%

080

1240

2440

3640

4860

51100

61390

7off

Table 12 Low-Pass Filter

Parameter Symbol Limit Values Unit Notes

min. max.

Corner frequency

variation Δ f - 20 + 20 %

TLE4998S

Signal Processing

Data Sheet 22 V 1.0, 2008-07

Figure 7 shows the filter characteristics as a magnitude plot (the highest setting is

marked). The “off” position would be a flat 0 dB line. The update rate after the low-pass

filter is 16 kHz.

Figure 7 DSP Input Filter (Magnitude Plot)

-6

-5

-4

-3

-2

-1

M agnit ude (dB)

Frequency (Hz)

TLE4998S

Signal Processing

Data Sheet 23 V 1.0, 2008-07

6.5 Clamping

The clamping function is useful for separating the output range into an operating range

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

output value OUT is limited to the clamping values.

The clamping values are calculated by:

Clamping value low (deactivated if CL=0):

Clamping value high (deactivated if CH=127):

Table 13 Clamping

Parameter Symbol Limit Values Unit Notes

min. max.

Clamping value low OUTCL 065535 LSB16 1)

1) For CL = 0 and CH = 127, the clamping function is disabled

Clamping value high OUTCH 065535 LSB16 1) 2)

2) OUTCL < OUTCH mandatory

Clamping quantization

steps

OUTCx 512 LSB16 3)

3) Quantization starts for CL at 0 LSB16 and for CH at 65535 LSB16

OUTCL CL 32 16⋅⋅=

OUTCH CH 1+()32 16 1–⋅⋅=

TLE4998S

Signal Processing

Data Sheet 24 V 1.0, 2008-07

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

is mapped to output values between 10240 LSB16 and 55295 LSB16.

Figure 8 Clamping Example

Note: The clamping high value must be above the low value. If OUTCL is set to a higher

value than OUTCH, the OUTCH value is dominating. This would lead to a constant

output value independent of the magnetic field strength.

0Bmin

B (mT)

Bmax

65535 Error range

Error range

Oper ating ra nge

OUTCH

OUT

(LSB16)

OUTCL

55295

10240

TLE4998S

Error Detection

Data Sheet 25 V 1.0, 2008-07

7 Error Detection

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

to the microcontroller in the status nibble (see Chapter 13).

7.1 Voltages Outside the Operating Range

The output signals an error condition if VDD crosses the overvoltage threshold level.

7.2 EEPROM Error Correction

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

error in another EEPROM line can also be detected, but not corrected. In an

uncorrectable EEPROM failure, the open drain stage is disabled and kept in the off state

permanently (high ohmic/sensor defect).

Table 14 Overvoltage

Parameter Symbol Limit Values Unit Notes

min. typ. max.

Overvoltage threshold VDDov 16.65 17.5 18.35 V1)

1) Overvoltage bit activated in status nibble, output stays in “off” state (high ohmic)

TLE4998S

Temperature Compensation

Data Sheet 26 V 1.0, 2008-07

8 Temperature Compensation

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

constant is specific for the different magnet types. Therefore, the TLE4998S 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, please refer to the signal processing flow in Figure 6.

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

with respect to 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 setting of the TC1, TC2, T0 values depend on the pre-calibrated values.

Table 15 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 TC1qTC115.26 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 TC2qTC20.119 ppm/ °C²

Reference temp. T0- 48 64 °C

Quantization steps of T0qT01°C 3)

3) Handled by algorithm only (see Application Note)

STC T() 1TC1TT

–()×TC2TT

–()

×++=

TLE4998S

Temperature Compensation

Data Sheet 27 V 1.0, 2008-07

8.1 Parameter Calculation

The parameters TC1 and TC2 may be calculated by:

Now the digital output for a given field BIN at a specific temperature can be calculated by:

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

S0 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) is given due to the magnetic

system. STC then needs 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 relationship:

TC1TL 160–

65536

---------------------- 1000000×=

TC2TQ 128–

8388608

----------------------- 1000000×=

OUT 2BIN

BFSR

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

×STCHall

×S04096××

⎝⎠

⎜⎟

⎛⎞

⋅OUTOS

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()≈

TLE4998S

Calibration

Data Sheet 28 V 1.0, 2008-07

9Calibration

For the calibration of the sensor, a special hardware interface to a PC is required. All

calibration and setting bits can be temporarily written into a Random Access Memory

(RAM). This allows the EEPROM to remain untouched during the entire calibration

process, since the number of the EEPROM programming cycles is limited. Therefore,

this temporary setup (using the RAM only) does not stress the EEPROM.

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

calibration to be performed in one step without iterations. After measuring the Hall output

signal for the two end points, the signal processing parameters Gain and Offset can be

calculated.

Table 16 Calibration Characteristics

Parameter Symbol Limit Values Unit Notes

min. max.

Ambient temperature at

calibration TCAL 10 30 °C

2 point Calibration

accuracy1)

1) Corresponds to ± 0.2% accuracy in each position

OUTCAL1 -8 8LSB12 Position 1

OUTCAL2 -8 8LSB12 Position 2

TLE4998S

Calibration

Data Sheet 29 V 1.0, 2008-07

9.1 Calibration Data Memory

When the MEMLOCK bits are programmed (two redundant bits), the memory c onten t is

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

out and the chip remains in application mode only, preventing accidental programming

due to environmental influences.

Figure 9 EEPROM Map

A matrix parity architecture allows 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.

Each bit in the even positions (0, 2, etc.) of all lines must sum up to an even number

(EVEN PARITY), and each bit in the odd positions (1, 3, etc.) must have an odd sum

(ODD PARITY). The parity column must have an even sum (EVEN PARITY).

This system of different parity calculations also protects against many block errors (such

as erasing a full line or even the whole EEPROM).

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

be updated. As for the column bits, the pre-calibration area must be read out and

considered for correct parity generation as well.

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

A detailed separate programming specification is available on request.

User-Calibration Bits

Pre- Calibr at ion Bit s

Column Parity Bits

R ow Par ity Bits

TLE4998S

Calibration

Data Sheet 30 V 1.0, 2008-07

9.2 Programming Interface

The VDD pin and the OUT pin are used as a two-wire interface to transmit the EEPROM

data to and from the sensor.

This allows:

• Communication with high data reliability

• The bus-type connection of several sensors and separate programming via the OUT

9.3 Data Transfer Protocol

The data transfer protocol is described in a separate document (User Programming

Description), available on request.

9.4 Programming of Sensors with Common Supply Lines

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

This redundancy makes it possibl e to continue operation in an emergency mode. If both

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

Table 17 Programming Characteristics

Parameter Symbol Limit Values Unit Notes

min. max.

Number of EEPROM

programming cycles NPRG -10 Cycles1)

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 10 ms ±1%, erase pulse 80 ms ±1%

Calibration memory -150 Bit All active EEPROM bits

Error Correction -26 Bit All parity EEPROM bits

TLE4998S

Application Circuit

Data Sheet 31 V 1.0, 2008-07

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 has to be connected directly to the

OUT pin.

The application circuit shown should be regarded as an example only. It will need to be

adapted to meet the requirements of other specific applications.

TLE

4998

optional

in1

in2

GND

47nF

1 nF

2k2

4.7nF

47nF

2k2

1 nF

4.7nF

µC

out

GND

TLE

4998

out

GND

Voltage Supply

Sensor Voltage Supply

µC

VDD

OUT1

GND

OUT2

Sensor

Module ECU

Module

TLE4998S

TLE4998S3 Package Outlines

Data Sheet 32 V 1.0, 2008-07

11 TLE4998S3 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

TLE4998S

TLE4998S4 Package Outlines

Data Sheet 33 V 1.0, 2008-07

12 TLE4998S4 Package Outlines

Figure 12 PG-SSO-4-1 (Plastic Green Single Small Outline Package)

1 MAX.

0.2

(0.25) 0.1 MAX.

1 x 45˚ 1.9 MAX.

±1˚

±0.08

5.16

±0.05

5.34

0.2+0.1

7˚

-0.1

±0.08

±0.06

3.71

3.38

0.25±0.05

±0.05

0.4

0.5

4x 0.6 MAX.

1.27 3 x 1.27 = 3.81

Total tolerance at 10 pitches ±1

) No solder function area

±0.3

±0.4

6.35 12.7

12.7±1

±0.5

-0.5

+0.75

4±0.3

GPO0535

-0.15

±0.1

Tape

Adhesiv

Tape

0.25

0.39

±0.5

(Useable Length)

(14.8)

23.8±0.5

38 MAX.

-1

1432

TLE4998S

SENT Output Definition (SAE J2716)

Data Sheet 34 V 1.0, 2008-07

13 SENT Output Definition (SAE J2716)

The sensor supports a basic version of the Single Edge Nibble Transmission (SENT)

protocol defined by SAE. The main difference between the standard version and its

implementation in the TLE4998 is the usage of an open drain instead of a push-pull

output.

13.1 Basic SENT Protocol Definition

• The single edge is defined by a 9-µs low pulse on the output, followed by the high

time defined in the protocol (nominal values, may vary by tolerance of internal RC

oscillator and the programming, see Section 13.2). All values are multiples of a 3-µs

unit time frame concept. A transfer consists of the following parts:A synchronization

period of 168 µs (in parallel, a new sample is calculated)

• A status nibble of 36-81 µs

• Three data nibbles of 36-81 µs (data packet 1 with a length of 108-243 µs)

• Three data nibbles of 36-81 µs (data packet 2 with a length of 108-243 µs)

• A CRC nibble of 36-81 µs

Figure 13 SENT Frame

The CRC checksum calculation includes the status nibble and the data nibbles. This

leads to a minimum transfer time of 456 µs, and a maximum transfer time of 816 µ s per

sample.

It is important to know that the sampling time (when values are taken for temperature

compensation) here is always defined as the beginning of the synchronization period;

during this period, the resulting data is always calculated from scratch.

compensate the sample transfer compensated sample

S a mp ling p o int:

values taken from

decima tion filter

Sensor processing

Output pin (physical)

Transferred data (logical)

sync. period Status

nibble

Data

nibble 1

Data

nibble 2

low

CRC

nibble

Data

nibble 1

mid

Next sampe

TLE4998S

SENT Output Definition (SAE J2716)

Data Sheet 35 V 1.0, 2008-07

As only one Hall value needs to be transferred within one sequence, the second data

package is divided into two parts (see Table 20):

• First, the remaining 4 LSBs of the Hall signals are transferred in the first data nibble.

This means the receiver may use the whole 16-bit data available in the sensor when

reading and using all 4 nibbles transferred.

• Second, the temperature is transferred as an 8-bit value. The value is transferred in

unsigned integer format and corresponds to -55°C to 200°C. For example, transferring

the value 55 corresponds to 0°C. The temperature is additional information and

although it is not calibrated, may be used for a plausibility check, for example.

The status nibble as defined in the SAE standard has two free bits (the LSBs or first and

second bit). These bits contain the selected magnetic range of the sensor and therefore

allow the received data to be interpret ed easily.

As no serial data is transferred with the IC, the r emaining bits of the status nibble are not

required. The MSB (fourth bit) notifying a start of a serial transmission and the data bit

(or third bit) would be kept zero. Thus, these bits are used in a more suitable way for this

sensor, as shown in Table 20.

In case of startup- or supply overvoltage condition, the open-drain stage is disabled

(high ohmic) and the corresponding status bits are set. After VDD has returned to the

normal operating range, this status information will be transmitted within the first SENT

transmission.

In case of uncorrectable EEPROM failure, the open-drain stage is disabled and is kept

in “switched off” state permanently (high ohmic/ sensor defect). The fourth bit is switched

to “1” for the first data package transferred after a reset. This allows the receiver to detect

low-voltage situations or EMC problems of the sensor. The third bit is set to “1” in case

of an over-voltage condition of the IC. This signals that a sensor is still functioning, but

its performance may be out of specification. It enables an early warning for high supply

voltage, before the sensor completely stops functioning (e.g. VDD > 17.5 V, see

Chapter 7.1).

Table 18 Mapping of Temperature Value

Junction Temperature Typ. Decimal Value from Sensor Note

- 55°C 0Theoretical lower limit1)

1) Theoretical range of temperature values, not operating temperature range

0°C 55

25°C 80

200°C 255 Theoretical upper limit1)

TLE4998S

SENT Output Definition (SAE J2716)

Data Sheet 36 V 1.0, 2008-07

13.2 Unit Time Setup

The basic SENT protocol unit time granularity is defined as 3 µs. Every timing is a

multiple of this basic time unit. To achieve more flexibility, trimming of the unit time can

be used to:

• Allow a calibration trim within a timing error of less than 20% clock error (as given in

SAE standard)

• Allow a modification of the unit time for small speed adjustments

This enables a setup of different unit times, even if the internal RC oscillator varies by

±20%. Of course, timing values that are too low could clash with timing requirements of

the application and should therefore be avoided, but in principle it is possible to adjust

the timer unit for a more precise protocol timing.

Table 19 Predivider Setting

The nominal unit time is calculated by:

Parameter Symbol Limit Values Unit Notes

min. max.

1) Useable predivider range is decimal 7 to 15. Prediv < 7 is internally ke pt at 7. Prediv default is decimal = 11 for

3 µs nominal unit time

Unit time tUNIT 2.0 4.0 µs ClkUNIT=8MHz2)

2) RC oscillator frequency variation +/- 20%

UNIT

= (Prediv × 2 + 2) / Clk

UNIT

Clk

UNIT

= 8MHz ±20%

TLE4998S

SENT Output Definition (SAE J2716)

Data Sheet 37 V 1.0, 2008-07

Table 20 Content of a SENT Data Frame (8 Nibbles)

11111111 1110 1111 655194094

11111111 1110 1110 65518

11111111 1110 : :

11111111 1110 0000 65504

11111111 1101 1111 655034093

4094

:: : : ::

00000000 0001 0000 161

00000000 0000 1110 14

00000000 0000 : :

00000000 0000 0001 1

00000000 0000 0000 00

00000000 0010 0000 322

00000000 0001 1111 31

00000000 0001 : :

00000000 0000 1111 150

1111

D1 MSN D1 Mi d N D1 LSN D2 MSN D2 M idN D2 LSN

bits description

state range

status and current range

s t art up c ondition in range R R

ov ervolt age in range RR

normal s t at e us ing range RR

bits description 2

D1 LSN D2MSN

deci m al: OUT

( = OUT12* 16+D2MSN )

1111 1111

1111 1110

1111 :

1111 0000

65535 (FSR )

65534

65520

D1 MidND1 M SN

description 1

deci m al : OUT

( = D1MSN *256 +D1MidN*16+D1LSN )

4095 (FSR )

4095

1110 1111 184 °C

: :

0101 0000

0100 1111 24 ° C

25 ° C

: : :

0000 0001 -54 °C

0011 0111 0°C

0011 0110

: :

-1°C

0000 0000 -55 °C

bits

D2MidN D2LSN

1111 1111

1111 1110

1111 :

1111 0000

description

dec imal: TEMP

( = D2MidN*16+D2LSN )

200 °C

199 °C

185 °C

SYNC STATUS

DATA WORD 1 DATA WORD 2

CRC

description

CRC calculation

for all nibbl es on the

basis of SAE J2716

seed v alue: 0101

polynomial: X

bits description

+/- 50mT

+/- 200mT

+/- 100mT

Abbreviations:

SYNC – synchronizati on nibbl e

STATUS – status nibble

CRC – cyclic redundancy code nibble

FSR – full scale range

MSN – most signifi cant nibbl e

MidN – middle nibbl e

LSN – least significant nibble

OUT

– 12 bit output v alue

OUT

– 16 bit output v alue

TEMP

– 8 bit temperature v alue

TLE4998S

SENT Output Definition (SAE J2716)

Data Sheet 38 V 1.0, 2008-07

13.3 Checksum Nibble Details

The Checksum nibble is a 4-bit CRC of the data nibbles including the status nibble. The

CRC is calculated using a polynomial x4 +x3 + x2 + 1 with a seed value of 0101.

In the TLE4998S it is implemented as a series of XOR and shift operations as shown in

the following flowchart:

Figure 14 CRC Calculation

A microcontroller implementation may use an XOR command plus a small 4-bit lookup

table to calculate the CRC for each nibble.

Figure 15 Example Code for CRC Generation

GENERATOR = 1101

SEED = 01 01 , use this

cons t ant as old CRC

value at first call

Pre-initialization:

VALUE

xor SEED

xor only if MSB = 1

VALUE

SEED

<<1

GENPOLY

xor

VALUE xor

SEED

CRC c alc u la t io n

Nibble

next Nibble

// Fast way for any µC with low memory and compute capabilities

char Data[8] = {…}; // contains the input data (status nibble , 6 data nibble , CRC)

// required variables and LUT

char CheckSum, i;

char CrcLookup[16] = {0, 13, 7, 10, 14, 3, 9, 4, 1, 12, 6, 11, 15, 2, 8, 5};

CheckSum= 5; // initialize checksum with seed "0101"

for (i=0; i<7; i++) {

CheckSum = CheckSum ^ Data[i];

CheckSum = CrcLookup[CheckSum];

}

; // finally check if Data [7] is equal to CheckSum

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