Operation is over 3.6 to 28V, with reduced function up to 42V, and the drvices have been developed with functional safety in mind.
“The device is developed compliant to ISO 26262, meeting all process requirements for ASIL-C, and hardware architectural metrics for ASIL-B according to ISO-26262-10:208E, clause 9”, the company told Electronics Weekly.
Processing comes from an on-board Arm Cortex-M0+ running at 24 or 48MHz.
While branding is ‘PSoC 4 HVPA-144K’, the actual part numbers are:
- CY8C4126LCE-HVxxx 24MHz, 64kbyte code flash, 4kbyte sram
- CY8C4127LCE-HVxxx 24MHz, 128byte code flash, 8kbyte sram
- CY8C4147LCE-HVxxx 48MHz, 128byte code flash, 8kbyte sram
Each also has 8kbyte of data flash and 1kbyte of supervisory flash (SFlash) for storing constants. All memories except the SFlash have ECC (error correction).
All three parts in the list have dual 16bit 48ksample/s ΔΣ ADCs, and each comes in three versions to give a choice of nominal accuracies: 0.25, 0.15 or 0.1%. A decimator is available to trade output sample rate with resolution up to 20bit or more.
“High-resolution sigma-delta ADCs, together with four digital filtering channels, enable accurate measurement of the battery’s state-of-charge and state-of-health by measuring key parameters such as voltage, current and temperature,” according to Infineon. “The device features two programmable gain amplifiers with automatic gain control, allowing fully autonomous control of the analogue front-end without software intervention. The use of shunt-based current sensing for batteries provides a higher accuracy than conventional Hall sensors.”
The automatic gain control is intended to work with a current-sensing shunt resistor and varies the input scaler across multiple fixed values between 4x and 512x. For voltage sensing, resistive input dividers are included to measure up to 19.2 or 28.8V full-scale.
Two more ADC channels are provided to sense temperature (internal or external) or other quantities.
Peripherals include four timer-counters that can produce PWM waveforms, a configurable serial communication block for I2C SPI or UART, and a LIN transceiver that can be connected directly to an external bus.
Packaging is 6 x 6mm 32pad QFN.
For software development, the company has its ‘AutoPDL’ automotive peripheral driver library and ‘SafeTlib’ safety library. “They are both A-Spice compliant, following the MISRA 2012 AMD1 and CERT C, and are ISO26262 compliant”, it said.
In the pipeline are related products for Li-ion batteries at low-voltage, and at 400V plus.
