mm908e622 Freescale Semiconductor, Inc, mm908e622 Datasheet - Page 38

• Manufacturer Part Number: mm908e622
• Description: Mm908e622 Integrated Quad Half-bridge, Triple High-side And Ec Glass Driver With Embedded Mcu And Lin For High End Mirror
• Manufacturer: Freescale Semiconductor, Inc

Half-Bridge Control
general enable of the circuitry is done by setting PSON in the
System Control Register (SYSCTL). The HBx_L and HBx_H
bits form one half bridge. It is not possible to switch on both
MOSFETs in one half-bridge at the same time. If both bits are
set, the high-side MOSFET is in PWM mode.
half-bridge being on at the same time, a break-before-make
circuit exists. Switching the high-side MOSFET on is inhibited
as long as the potential between gate and V
certain threshold. Switching the low-side MOSFET on is
blocked as long as the potential between gate and source of
the high-side MOSFET did not fall below a certain threshold.
HALF-BRIDGE OUTPUT REGISTER (HBOUT)
HBx_H, HBx_L — Half Bridge Output Switches
output according to the following table.
Reset clears all HBx_H, HBx_L bits.
Half-Bridge PWM mode
HBxH of one Half-bridge to “1”. In this mode the high-side
MOSFET is controlled by the incoming PWM signal on the
PWM terminal (see
switched on.
38
908E622
Functional Device Operation
Operational Modes
Reset
Read
Write
HBx_H
Each output MOSFET can be controlled individually. The
To avoid both MOSFETs (high-side and low-side) of one
These read/write bits select the output of each half-bridge
The PWM mode is selected by setting both HBxL and
If the incoming signal is high, the high-side MOSFET is
0
0
1
1
HB4_H
Bit7
Register Name and Address: HBOUT - $01
0
HBx_L
Table 9. Half-Bridge Configuration
0
1
0
1
HB4_L
6
0
Figure
Low-side and high-side MOSFET off
High-side MOSFET off,
low-side MOSFET on
High-side MOSFET on,
low-side MOSFET off
High-side MOSFET in PWM mode
HB3_H
5
0
2, page 2).
HB3_L
4
0
HB2_H
3
0
Mode
HB2_L
SS
2
0
is not below a
HB1_H
1
0
HB1_L
Bit0
0
switched off.
Half-Bridge Status and Control Register (HBSCTL) the
recirculation behavior in PWM mode can be controlled. If
CRM is set the corresponding low-side MOSFET is switched
on if the PWM controlled high-side MOSFET is off.
Half-Bridge Current Recopy
allow a current recopy feature. These sense sources are
internally amplified and switched to the Analog Multiplexer.
selected via bit CSA in the A0MUCTL register (see
Half-Bridge Overtemperature Protection
conditions. Each power output comprises two different
temperature thresholds.
If the temperature reaches this threshold the HTIF bit in the
Interrupt Flag Register (IFR) is set and an interrupt will be
initiated if HTIE bit in the Interrupt Mask register is set. In
addition this interrupt can be used to automatically turn off the
power stages. This shutdown can be enabled/disabled by
Bits HTIS0-1 in the System Control Register (SYSCTL).
the outputs reenabled) by writing a “1” to the HTIF flag in the
Interrupt Flag Register (IFR) or by a reset. Clearing this flag
has no effect as long as a high temperature condition is
present.
temperature reset (HTR) will be used to turn off all power
stages (HB (all Fet’s), HS, HVDD, EC, H0) in order to protect
the device.
Half-Bridge Overcurrent Protection
VSUP and load shorts. The overcurrent protection is
implemented on each HB. If a overcurrent condition on the
high-side MOSFET occurs the high-side MOSFET is
automatically switched off. An overcurrent condition on the
low-side MOSFET will automatically turn off the low-side
MOSFET. In both cases the corresponding HBxOCF flag in
the Half-Bridge Status and Control Register (HBSCTL) is set.
corresponding Half-Bridge MOSFETs reenabled) by writing a
“1” to the HBxOCF in the Half-Bridge Status and Control
Register (HBSCTL) or by a reset.
If the incoming signal is low, the high-side MOSFET is
With the current recirculation mode control bit CRM in the
Each low-side MOSFET has an additional sense output to
The factor for the Current Sense amplification can be
CSA = “1”: low resolution selected
CSA = “0”: high resolution selected
The outputs are protected against overtemperature
The first threshold is the high temperature interrupt (HTI).
The high temperature interrupts flag (HTIF) is cleared (and
If the HTI shutdown is disabled, a second threshold high
The Half-Bridges are protected against short to GND,
The overcurrent status flag is cleared (and the
Analog Integrated Circuit Device Data
Freescale Semiconductor
page
32)