TPIC8101 Knock Sensor Interface
1 Features
- Qualified for Automotive Applications
- AEC-Q100 Qualified With the Following Results:
- Device Temperature Grade 1: –40°C to 125°C Ambient Operating Temperature Range
- Device HBM Classification Level 3A
- Device CDM Classification Level C6
- Dual-Channel Knock Sensor Interface
- Programmable Input Frequency Prescaler (OSCIN)
- Serial Interface With Microprocessor (SPI)
- Programmable Gain
- Programmable Band-Pass Filter Center Frequency
- External Clock Frequencies up to 24 MHz
- 4, 5, 6, 8, 10, 12, 16, 20, and 24 MHz
- Programmable Integrator Time Constants
- Operating Temperature Range −40°C to 125°C
2 Applications
- Engine Knock Detector Signal Processing
- Analog Signal Processing With Filter Characteristics
3 Description
The TPIC8101 is a dual-channel signal processing IC for detection of premature detonation in combustion engine. The two sensor channels are selectable through the SPI bus. The knock sensor typically provides an electrical signal to the amplifier inputs. The sensed signal is processed through a programmable band-pass filter to extract the frequency of interest (engine knock or ping signals). The band-pass filter eliminates any engine background noise associated with combustion. The engine background noise is typically low in amplitude compared to the predetonation noise.
The detected signal is full-wave rectified and integrated by use of the INT/HOLD signal. The digital output from the integration stage is either converted to an analog signal, passed through an output buffer, or be read directly by the SPI.
This analog buffered output may be interfaced to an A/D converter and read by the microprocessor. The digital output may be directly interfaced to the microprocessor.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (NOM) |
|---|---|---|
| TPIC8101 | SOIC (20) | 7.50 mm × 12.80 mm |
- For all available packages, see the orderable addendum at the end of the data sheet.
Simplified Schematic
4 Revision History
Changes from B Revision (December 2014) to C Revision
- Added qualification for automotive applications to FeaturesGo
- Added the ESD Ratings table with HBM and CDM ratings Go
Changes from A Revision (May 2005) to B Revision
- Added Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section.Go
5 Description (continued)
The data from the A/D enables the system to analyze the amount of retard timing for the next spark ignition timing cycle. With the microprocessor closed-loop system, advancing and retarding the spark timing optimizes the load/RPM conditions for a particular engine (data stored in RAM).
