908E625_07 Datasheet, PDF (36/48 Pages) Freescale Semiconductor, Inc – Integrated Quad Half H-Bridge with Power Supply, Embedded MCU, and LIN Serial Communication

FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
H-Bridges Current Sense Amplification Select Bit (CSA)
This read/write bit selects the current sense amplification
of the H-Bridges. Reset clears the CSA bit.
• 1 = Current sense amplification set for measuring 0.5 A.
• 0 = Current sense amplification set for measuring 2.5 A.
H-Bridge Current Limitation Selection Bits (CLS2:CLS0)
These read/write bits select the current limitation value
according to Table 10. Reset clears the CLS2:CLS0 bits.
Table 10. H-Bridge Current Limitation Value Selection
Bits
CLS2 CLS1 CLS0
Current Limit
0
0
0
0
0
1
No Limit
0
1
0
0
1
1
55 mA (typ)
1
0
0
260 mA (typ)
1
0
1
370 mA (typ)
1
1
0
550 mA (typ)
1
1
1
740 mA (typ)
HIGH-SIDE DRIVER
The high-side output is a low-resistive high-side switch
targeted for driving lamps. The high side is protected against
overtemperature. To limit the high inrush current of bulbs,
overcurrent protection circuitry is used to limit the current.
The output is enabled with bit PSON in the System Control
Register and can be switched on/off with bit HS_ON in the
Power Output Register. Figure 21 depicts the high-side
switch circuitry and connection to external lamp.
HIGH-SIDE OVERVOLTAGE/UNDERVOLTAGE
PROTECTION
The high-side output pin, HS, is protected against
undervoltage/overvoltage conditions. This protection is done
by the low- and high-voltage interrupt circuitry. If one of these
flags (LVF, HVF) is set, the output is disabled.
The overvoltage/undervoltage status flags are cleared
and the output re-enabled by writing a Logic [1] to the LVF/
HVF flags in the Interrupt Flag Register or by reset. Clearing
this flag is useless as long as a high- or low-voltage condition
is present.
VSUP
Control
On/Off
Status
Current
Limit
High-Side Driver
Charge Pump,
Overcurrent Protection,
Inrush Current Limiter
HS
Figure 21. High-Side Circuitry
908E625
36
Analog Integrated Circuit Device Data
Freescale Semiconductor