AMIS30512C5122RG ON Semiconductor, AMIS30512C5122RG Datasheet - Page 17

• Manufacturer Part Number: AMIS30512C5122RG
• Description: IC MOTOR DVR MICRO STEP 24SOIC
• Manufacturer: ON Semiconductor

Specifications of AMIS30512C5122RG

• 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)
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Speed and Load Angle Output
level of the Back−e.m.f. voltage of the motor. This
Back−e.m.f. voltage is sampled during every so−called “coil
coil during current decay, the coil voltage V
transient behavior. As this transient is not always desired in
application software, two operating modes can be selected
by means of the bit <SLAT> (see “SLA−transparency” in
Table 15: SPI Control Register 2). The SLA pin shows in
“transparent mode” full visibility of the voltage transient
behavior. This allows a sanity−check of the speed−setting
versus motor operation and characteristics and supply
voltage levels. If the bit “SLAT” is cleared, then only the
voltage samples at the end of each coil current zero crossing
are visible on the SLA−pin. Because the transient behavior
The SLA−pin provides an output voltage that indicates the
Because of the relatively high recirculation currents in the
V
I
COIL
V
COIL
BB
Micro−step
Previous
Figure 12. Principle of Bemf Measurement
COIL
I COIL
Current Decay
Coil Current Zero Crossing
shows a
http://onsemi.com
Voltage Transient
Zero Current
ZOOM
17
current zero crossings”. Per coil, two zero−current positions
exist per electrical period, yielding in total four zero−current
observation points per electrical period.
of the coil voltage is not visible any more, this mode
generates smoother Back e.m.f. input for post−processing,
e.g. by software.
output level (0 to 5 V), the sampled coil voltage V
divided by 2 or by 4. This divider is set through an SPI bit
<SLAG>. (Table 15: SPI Control Register 2)
SLA−pin and the transparency−bit. “PWMsh” and
“Icoil=0” are internal signals that define together with SLAT
the sampling and hold moments of the coil voltage.
In order to bring the sampled Back e.m.f. to a descent
The following drawing illustrates the operation of the
V BEMF
Micro−step
Next
V
BEMF
t
t
t
COIL
is