Datasheet

NXP Semiconductors 27
10XS3435
6.3 Functional internal block description
Figure 9. Functional block diagram
6.3.1 Power supply
The 10XS3435 is designed to operate from 4.0 to 28 V on the VPWR pin. Characteristics are provided from 6.0 to 20 V for the device.
The VPWR pin supplies power to internal regulator, analog, and logic circuit blocks. The VDD supply is used for Serial Peripheral Interface
(SPI) communication in order to configure and diagnose the device. This IC architecture provides a low quiescent current sleep mode.
Applying V
PWR
and V
DD
to the device will place the device in the Normal mode. The device will transit to Fail-safe mode in case of failures
on the SPI or/and on VDD voltage.
6.3.2 High-side switches: HS0–HS3
These pins are the high-side outputs controlling automotive lamps located for the front of vehicle, such as 65 W/55 W bulbs and Xenon-
HID modules. Those N-channel MOSFETs with 10
mOhm & 35 mOhm R
DS(on)
are self-protected and present extended diagnostics in
order to detect bulb outage and short-circuit fault condition. The HS output is actively clamped during turn off of inductive loads and
inductive battery line. When driving DC motor or Solenoid
loads demanding multiple switching, an external recirculation device must be used to maintain the device in its Safe Operating Area.
6.3.3 MCU interface and output control
In Normal mode, each bulb is controlled directly from the MCU through SPI. A pulse width modulation control module allows improvement
of lamp lifetime with bulb power regulation (PWM frequency range from 100 to 400
Hz) and addressing the dimming application (day
running light). An analog feedback output provides a current proportional to the load current or the temperature of the board. The SPI is
used to configure and to read the diagnostic status (faults) of high-side outputs. The reported fault conditions are: openload, short-circuit
to battery, short-circuit to ground (overcurrent and severe short-circuit), thermal shut-down, and under/overvoltage. Thanks to accurate
and configurable overcurrent detection circuitry and wire-harness optimization, the vehicle is lighter.
In Fail-safe mode, each lamp is controlled with dedicated parallel input pins. The device is configured in default mode.
Power Supply
MC10XS3435 - Functional Block Diagram
Parallel Control Inputs
MCU Interface & Output Control
SPI Interface
Self-protected
Supply MCU Interface & Output Control Self-protected High-side Switches
PWM Controller
High-side
Switches
HS0-HS3
MCU
Interface