Atmel ATA6264 - Manual (Page 3)

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4929B–AUTO–01/07
ATA6264 [Preliminary]
1.1 Block Description
1.1.1 Integrated Boost Converter EVZ
With an external n-channel FET, the integrated boost converter EVZ provides 3 different volt-
ages adjustable via the serial interface for the energy reserve and firing capacitors. Two
voltages are fixed values; one voltage can be adjusted using an external resistive divider.
1.1.2 Integrated Buck Converter VSAT
The integrated buck converter VSAT is a fully integrated step-down converter supplied by the
boost converter, EVZ, and providing 7.8V, 9.1V, or 10.4V. The user can program the voltage via
an OTP system.
1.1.3 Integrated Buck Converter VCORE
The integrated buck converter VCORE is a fully integrated step-down converter supplied either
by the boost converter, EVZ, or by the battery, and providing 1.88V, 2.5V, or 5V. The user can
program the voltage via an OTP system.
1.1.4 Linear Regulator VPERI
The linear regulator, VPERI, is supplied from the buck converter VSAT and provides an accurate
voltage of 3.3V ±3% or 5V ±4% as a supply for sensitive elements such as sensors and ADC
references with the current capability of 100 mA. The user can program the voltage via an OTP
system. With a sophisticated power-sequencing concept of VCORE and VPERI, ATA6264 sup-
ports dual-voltage-supply microcontrollers, so that under all conditions the voltage difference
between the two linear regulator voltages never drops below a defined value. This measure
guarantees the safe operation of the system.
1.1.5 Blocks Included
• A general purpose comparator USP, for, for example, low battery voltage detection
• A band gap as reference for all internal voltages and currents
• Two ISO9141 interfaces, one of which is configurable via OTP in accordance with the LIN
specification
• Five constant voltage sources with current-to-voltage mirrors used for resistance
measurements, such as buckle switch detection in the range from –0.5 mA to –40 mA
• An AMUX block with push-pull buffer stage provides the output of all analog values such as
voltage sources, low voltage detection, or the chip temperature for continuous diagnosis
• A 16-bit serial interface for the communication with the microcontroller which includes a 16-bit
shift register, a 16-bit latch, and a decoder-logic block
• A watchdog to monitor the microcontroller and to generate reset signals in the case of failure
• Internal oscillator generates internal clock signals
• GKEY function to control the main switch of the ECU via a logic signal