AMIS30512C5122G ON Semiconductor, AMIS30512C5122G Datasheet - Page 10

• Manufacturer Part Number: AMIS30512C5122G
• Description: IC MOTOR DVR MICRO STEP 24SOIC
• Manufacturer: ON Semiconductor

Specifications of AMIS30512C5122G

• Applications: Stepper Motor Driver, 2 Phase
• Number Of Outputs: 1
• Current - Output: 800mA
• Voltage - Supply: 6 V ~ 30 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-SOIC (7.5mm Width)
• Operating Temperature Classification: Automotive
• Package Type: SOIC
• Operating Supply Voltage (min): 4.75V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.25V
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Load: -
• Lead Free Status / Rohs Status: Compliant

H−Bridge Drivers
windings. Each H−bridge consists of two low−side and two
high−side N−type MOSFET switches. Writing logic ‘0’ in
bit <MOTEN> disables all drivers (high−impedance).
Writing logic ‘1’ in this bit enables both bridges and current
can flow in the motor stator windings.
switches, it is guaranteed that the top− and bottom−switches
of
simultaneously (interlock delay).
implemented. In a first stage, the current in the driver is
limited. Secondly, when excessive voltage is sensed across
the transistor, the transistor is switched−off.
voltage slope control is implemented in the output switches.
The output slope is defined by the gate−drain capacitance of
output transistor and the (limited) current that drives the
gate. There are two trimming bits for slope control
(Table 25: SPI Control Parameter Overview EMC[1:0]).
diodes”: when a current is forced through the transistor
switch in the reverse direction, i.e. from source to drain, then
the transistor is switched on. This ensures that most of the
current flows through the channel of the transistor instead of
through the inherent parasitic drain−bulk diode.
duty cycle of the PWM is adapted automatically to >50% to
maintain the requested average current in the coils. This
process is completely automatic and requires no additional
A full H−bridge is integrated for each of the two stator
In order to avoid large currents through the H−bridge
A two−stage protection against shorts on motor lines is
In order to reduce the radiated/conducted emission,
The power transistors are equipped with so−called “active
In case the supply voltage is lower than 2*Bemf, then the
the
same
Icoil
0
half−bridge
T
Set value
PWM
are
Forward & Slow Decay
Figure 7. Forward and Slow/Fast Decay PWM
never
Fast Decay & Forward
conductive
Functional Description
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micro−step position at hand, the Rdson of the low−side
transistors will be adapted such that excellent current−sense
accuracy is maintained. The Rdson of the high−side
transistors remain unchanged, see Table 4: DC Parameters
for more details.
PWM Current Control
winding current with the requested current and feeds back
the information to a digital regulation loop. This loop then
generates a PWM signal, which turns on/off the H−bridge
switches. The switching points of the PWM duty−cycle are
synchronized to the on−chip PWM clock. The frequency of
the PWM controller can be doubled and an artificial jitter
can be added (Table 14: SPI Control Register 1). The PWM
frequency will not vary with changes in the supply voltage.
Also variations in motor−speed or load−conditions of the
motor have no effect. There are no external components
required to adjust the PWM frequency.
Automatic Forward and Slow−Fast Decay
combination of forward and slow−decay. The absence of
fast−decay in this mode, guarantees the lowest possible
current−ripple “by design”. For transients to lower current
levels, fast−decay is automatically activated to allow
high−speed response. The selection of fast or slow decay is
completely transparent for the user and no additional
parameters are required for operation.
parameters for operation. The over−all current−ripple is
divided by two if PWM frequency is doubled (Table 14: SPI
Control Register 1).
Depending on the desired current range and the
A PWM comparator compares continuously the actual
The PWM generation is in steady−state using a
Actual value
Forward & Slow Decay
t