908E626_09 Datasheet, PDF (25/44 Pages) Freescale Semiconductor, Inc – Integrated Stepper Motor Driver with Embedded MCU and LIN Serial Communication

FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
HVDDON — HVDD On Bit
This read/write bit enables HVDD output. Reset clears the
HVDDON bit.
• 1 = HVDD enabled.
• 0 = HVDD disabled.
HALF-BRIDGES
Outputs HB1 : HB4 provide four low resistive half-bridge
output stages. The half-bridges can be used in H-bridge, high
side, or low side configurations.
Reset clears all bits in the H-bridge Output Register
(HBOUT) owing to the fact that all half-bridge outputs are
switched off.
HB1: HB4 output features:
• Short circuit (over-current) protection on high side and
low side MOSFETs.
• Current recopy feature (low side MOSFET).
• Over-temperature protection.
• Over-voltage and under-voltage protection.
• Current limitation feature (low side MOSFET).
VSUP
On/Off
Status
High-Side Driver
Charge Pump,
Overtemperature Protection,
Overcurrent Protection
Control
BEMF
On/Off
Status
Current
Limit
Low-Side Driver
Current Recopy,
Current Limitation,
Overcurrent Protection
HBx
GND
Figure 12. Half-bridge Push-Pull Output Driver
Half-Bridge Control
Each output MOSFET can be controlled individually. The
general enable of the circuitry is done by setting PSON in the
System Control Register (SYSCTL). HBx_L and HBx_H 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 has a higher priority.
To avoid both MOSFETs (high side and low side) of one
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_SS is not below a
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)
Register Name and Address: HBOUT - $01
Bit7 6
5
4
3
2
1 Bit0
Read _{HB4_ HB4_ HB3_ HB3_ HB2_ HB2_ HB1_ HB1_}
Write ^H
L
H
L
H
L
H
L
Reset 0
0
0
0
0
0
0
0
Analog Integrated Circuit Device Data
Freescale Semiconductor
908E626
25