Data Sheet

11

1.10

2018-09-13

TLE4929C Crankshaft Sensor

Fully Programmable Crankshaft Sensor

3

Functional Description

3.1

Definition of the Magnetic Field Direction

Figure 3

Definition of the Positive Magnetic Field Direction

3.2

Block Diagram

Figure 4

Block Diagram

3.3

Basic Operation

The basic operation of the TLE4929C is to transpose the magnetic field produced by a spinning target wheel

into speed pulses with directional information at the output pin. The pulse width indicates forward or

backward direction information and can be adjusted in EEPROM-options. It is also possible to parameterize

output switching without direction information like it is requested for differential CAM-shaft sensors.The

correspondence between field polarity and output polarity can be set according to the application needs as

well. By definition a magnetic field is considered as positive if the magnetic North Pole is placed at the rear

side of the sensor, see Figure 3.

For understanding the operation five different phases have to be considered:

•

Power-on phase

S

Tooth

Notch

Notch

IC Branded

Side

S

IC Branded

Side

Tooth

Notch

Notch

Digital-Core:

Min/Max -detection

Offset-calculation

Hysteresis-calculation

System-watchdog

Time-watchdog

Offset compensation

Direction detection

Stop-start circuit

EEPROM-control

Output-protocol

VDD-comunication

Q

GND

VDD

Open

Drain

(protected)

EEPROM

Regulator (digital)

Regulator (bandgap + analog)

Regulator (chopped Hall elements)

A / D

BB_DAC

A / D

BB_DAC

A / D

d_ODAC

A / D

speed

A / D

cODAC

A / D

direction