MM908E625ACDWB Freescale Semiconductor, MM908E625ACDWB Datasheet - Page 34

• Manufacturer Part Number: MM908E625ACDWB
• Description: IC QUAD HALF BRDG MCU/LIN 54SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MM908E625ACDWB

• Applications: Automotive Mirror Control
• Core Processor: HC08
• Program Memory Type: FLASH (16 kB)
• Controller Series: 908E
• Ram Size: 512 x 8
• Interface: SCI, SPI
• Number Of I /o: 13
• Voltage - Supply: 8 V ~ 18 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 54-SOIC (0.300", 7.50mm Width) Exposed Pad
• Program Memory Size: 16 KB
• Number Of Programmable I/os: 54
• Number Of Timers: 16
• Operating Supply Voltage: - 18 V to + 28 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

OFFSET CHOPPING
set, HB1 and HB2 will continue to switch on the low-side
MOSFETs with the rising edge of the FGEN signal and HB3
and HB4 will switch on the low-side MOSFETs with the falling
HALF-BRIDGE CURRENT RECOPY
allow a current recopy feature. This sense source is internally
connected to a shunt resistor. The drop voltage is amplified
and switched to the analog multiplexer.
selected via bit CSA in the System Control Register.
34
908E625
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Coil1 Current
Coil2 Current
If bit OFC_EN in the H-Bridge Control Register (HBCTL) is
Each low-side MOSFET has an additional sense output to
The factor for the current sense amplification can be
• CSA = 1: Low resolution selected (500 mA
• CSA = 0: High resolution selected (2.5 A measurement
(MCU PWM
FGEN Input
VSUP Line
Current in
Signal)
measurement range)
range)
Figure 19. Offset Chopping for Step Motor Control
feature allows the reduction of EMI due to a reduction of the
di/dt
HALF-BRIDGE BEMF GENERATION
detected in any half-bridge. This recirculation current flows
via the two freewheeling diodes of the power MOSFETs. The
BEMF circuitry detects that and generates a HIGH on the
BEMF output as long as a recirculation current is detected.
This signal provides a flexible and reliable detection of stall in
step motor applications. For this the BEMF circuitry takes
advantage of the instability of the electrical and mechanical
behavior of a step motor when blocked. In addition the signal
can be used for open load detection (absence of this signal),
see
edge on the FGEN input. In step motor applications this
The BEMF output is set to 1 if a recirculation current is
Figure
(Figure
20.
19).
Analog Integrated Circuit Device Data
Freescale Semiconductor
HB1
HB2
HB3
HB4
Coil2…..
Coil1…..