datasheetbank_Logo
Integrated circuits, Transistor, Semiconductors Search and Datasheet PDF Download Site

908E625 View Datasheet(PDF) - Freescale Semiconductor

Part Name
Description
View to exact match
908E625 Datasheet PDF : 48 Pages
First Prev 21 22 23 24 25 26 27 28 29 30 Next Last
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
ANALOG DIE I/OS
LIN Physical Layer
The LIN bus pin provides a physical layer for single-wire
communication in automotive applications. The LIN physical
layer is designed to meet the LIN physical layer specification.
The LIN driver is a low-side MOSFET with internal current
limitation and thermal shutdown. An internal pull-up resistor
with a serial diode structure is integrated, so no external pull-
up components are required for the application in a slave
node. The fall time from dominant to recessive and the rise
time from recessive to dominant is controlled. The symmetry
between both slew rate controls is guaranteed.
The LIN pin offers high susceptibility immunity level from
external disturbance, guaranteeing communication during
external disturbance.
The LIN transmitter circuitry is enabled by setting the
PSON bit in the System Control Register (SYSCTL). If the
transmitter works in the current limitation region, the LINCL
bit in the System Status Register (SYSSTAT) is set. Due to
excessive power dissipation in the transmitter, software is
advised to monitor this bit and turn the transmitter off
immediately.
TXD PIN
The TXD pin is the MCU interface to control the state of the
LIN transmitter (see Figure 1). When TXD is LOW, LIN output
is low (dominant state). When TXD is HIGH, the LIN output
MOSFET is turned off. The TXD pin has an internal pull-up
current source in order to set the LIN bus in recessive state
in the event, for instance, the microcontroller could not control
it during system power-up or power-down.
RXD PIN
The RXD transceiver pin is the MCU interface, which
reports the state of the LIN bus voltage. LIN HIGH (recessive
state) is reported by a high level on RXD, LIN LOW (dominant
state) by a low level on RXD.
STOP MODE/WAKE-UP FEATURE
During STOP mode operation the transmitter of the
physical layer is disabled. The receiver pin is still active and
able to detect wake-up events on the LIN bus line.
If LIN interrupt is enabled (LINIE bit in the Interrupt Mask
Register is set), a falling edge on the LIN line causes an
interrupt. This interrupt switches on the main voltage
regulator and generates a system wake-up.
Analog Multiplexer/ADOUT Pin
The ADOUT pin is the analog output interface to the ADC
of the MCU. See Figure 12. An analog multiplexer is used to
read seven internal diagnostic analog voltages.
Current Recopy
The analog multiplexer is connected to the four low-side
current sense circuits of the half-bridges. These sense
circuits offer a voltage proportional to the current through the
low-side MOSFET. High or low resolution is selectable:
5.0 V/2.5 A or 5.0 V/500 mA, respectively. Refer to Half-
Bridge Current Recopy on page 34.)
Analog Input PA1
The analog input PA1 is directly connected to the analog
multiplexer, permitting analog values from the periphery to be
read.
TEMPERATURE SENSOR
The 908E625 includes an on-chip temperature sensor.
This sensor offers a voltage that is proportional to the actual
chip junction temperature.
VSUP PRESCALER
The VSUP prescaler permits the reading or measurement
of the external supply voltage. The output of this voltage is
VSUP / RATIOVSUP.
The different internal diagnostic analog voltages can be
selected with the ADMUX Register.
ANALOG MULTIPLEXER CONFIGURATION
REGISTER (ADMUX)
Bit s
Read
Write
Reset
Register Name and Address: ADMUX - $07
7
6
5
4
3
2
1
0
0
0
0
0
SS3 SS2 SS1 SS0
0
0
0
0
0
0
0
0
SS3, SS2, SS1, and SS0—A/D Input Select Bits
These read/write bits select the input to the ADC in the
microcontroller according to Table 7. Reset clears SS3, SS2,
SS1, and SS0 bits.
Analog Integrated Circuit Device Data
Freescale Semiconductor
908E625
25
 

Share Link: 

datasheetbank.com [ Privacy Policy ] [ Request Datasheet ] [ Contact Us ]