Document Number: MC33909
Rev. 4.0, 8/2016
NXP Semiconductors
Advance Information
System basis chip with DC/DC and
multiple switch-to-ground interface
33909
This SMARTMOS IC integrates the common functionality of system basis chips
with switch detection inputs. The device works as an advanced power
management unit for the MCU and additional integrated circuits such as
sensors, CAN transceivers, and eXtreme switches. It has one built-in enhanced
high-speed CAN interface (ISO 11898-2 and -5), with local and bus failure
diagnostics, protection and fail-safe operation mode, and includes four LINs,
compatible with specification 2.1 and SAEJ2602-2.
SYSTEM BASIS CHIP
The IC starts operating when the VBATP (reverse battery protected) pin
reaches 5.3 V maximum. The device requires a reverse blocking ultrafast or
Schottky diode for operation. The VPRE supply operating in Buck/Boost mode
allows functional operation of the IC from 2.5 V to 35 V on VBATP. The VPRE
pin supplies the source voltage for the VDD, VAUX, CAN5V, and SG power
rails.
AD SUFFIX (PB-FREE)
48 PIN LQFP-EP
98ASA00737D
Switch-to-ground inputs are available for switch detection and supply
configurable pulsed wetting current, with low sustain current levels for
improved thermal and power management. The IC can be programmed to
wake-up when a change of state is detected on any input. The device also
implements an innovative and advanced fail-safe state machine and concept
solution.
Applications
• Front/rear body controllers
• Gateway modules
• Electric power steering
• Power train
Features
• VDD rail (3.3 V or 5.0 V) operates down to 2.5 V on VBATP (provided by
VPRE Buck/Boost)
• VAUX rail (3.3 V or 5.0 V) capable of surviving short-to-battery (40 V)
conditions
• Low Q current operation for low-power sleep mode, typ. 125 μA
• Secured SPI and advanced watchdog
• SAFE_B pin for limp home mode
• Six switch to GND inputs with selectable wake-up in change of state
• Analog multiplexer
VPRE VAUXE VAUXB
VSW VPREGATE
VAUX
VDDE
VBAT
BOOT
PI Filter
VBAT_SMPS
VDDB
VDD
VDD
VBATP
VBAT
VBATSNS
WDI
SAFE_B
AMUX
SG0
SG1
SG2
SG3
SG4
SG5
RST_B
INT_B
MCU
MOSI
MISO
SCLK
CS_B
SPI
CANH
CANL
CAN Bus
RXD_L0:RXD_L3
TXD_L0:TXD_L3
VBATP
RXD_C
TXD_C
LIN_0
LIN_1
LIN_2
LIN_3
LIN Bus
LIN Bus
LIN Bus
LIN Bus
CAN5V
GND LIN
GND
CANGND
Figure 1. 33909AD simplified application diagram
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
© 2016 NXP B.V.