Overview
The CS4192XDWF16, produced by ON Semiconductor, is a monolithic BiCMOS integrated circuit designed to drive air-core meters commonly used in automotive applications such as speedometers and tachometers. This device translates a digital 10-bit word from a microprocessor or microcontroller into complementary DC outputs that control the quadrature coils of the meter. The CS4192 features a tangential drive algorithm, which enhances the torque of the meter movement, reducing errors at critical angles.
Key Specifications
| Characteristic | Test Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply Voltage (VBB) | -1.0 | 16.5 | V | ||
| Supply Voltage (VCC) | -1.0 | 6.0 | V | ||
| Steady State Output Current | -100 | 100 | mA | ||
| Operating Junction Temperature (TJ) | 150 | °C | |||
| Storage Temperature Range | -65 | 150 | °C | ||
| Output Function Accuracy | -1.2 | ±0.5 | 1.2 | deg | |
| Output Shutdown Current, Source (VBB = 14 V) | 70 | 125 | 250 | mA | |
| Thermal Shutdown | 170 | °C | |||
| Shift Clock Frequency | 2.0 | MHz |
Key Features
- Serial Input Bus using SPI compatible serial connection up to 2.0 MHz shift clock rate
- Tangential Drive Algorithm for enhanced torque and accuracy
- 70 mA Drive Circuits for each coil
- 0.5° Accuracy (Typical)
- Power-On-Reset (POR)
- Protection Features:
- Output Short Circuit Protection
- Overtemperature Protection
- Internally Fused Leads in SOIC-16 WB Package
- Pb-Free Packages Available
Applications
The CS4192 is primarily used for interfacing between a microcontroller or microprocessor and air-core meter movements in automotive vehicles. These applications include speedometers and tachometers. The device drives the meter’s pointer by generating the appropriate DC coil voltages based on the digital input from the microcontroller, ensuring precise and accurate readings.
Q & A
- What is the primary function of the CS4192?
The CS4192 translates a digital 10-bit word from a microprocessor or microcontroller into complementary DC outputs to drive air-core meters.
- What is the tangential drive algorithm used in the CS4192?
The tangential drive algorithm enhances the torque of the meter movement by approximately 40% at critical angles compared to a sin-cos algorithm.
- What is the resolution and accuracy of the CS4192?
The CS4192 provides a 0.35° resolution and ±1.2° accuracy over the full 360° range of the gauge.
- How does the CS4192 protect against fault conditions?
The CS4192 features overcurrent protection (up to 125 mA) and overtemperature protection (up to 170°C), disabling the output drivers in case of a fault.
- What is the maximum operating frequency of the serial clock?
The serial clock can operate up to 2.0 MHz.
- How are the output buffers controlled?
The output buffers are controlled by a common OE enable pin; they are turned off when OE is low and enabled when OE is high before the falling edge of CS.
- What is the purpose of the status pin (ST)?
The status pin (ST) reflects the state of the outputs and is low whenever the outputs are disabled, either by OE or the internal protection circuitry.
- Can the CS4192 be cascaded with other devices?
Yes, the CS4192 allows cascading of multiple devices on a common serial port through the serial data output (SO) pin.
- What are the package options for the CS4192?
The CS4192 is available in SOIC-16 WB packages, including Pb-free options.
- How does the power-up sequence work for the CS4192?
The IC requires a pulse on the Chip Select (CS) pin to clear the Status Fault (ST) after power-up, and OE must be high before the falling edge of CS to enable the output buffers.
