
MC3PHAC/D
Pin Descriptions
MOTOROLA
3-Phase AC Motor Controller
7
Pin Descriptions
Table 2
is a pin-by-pin functional description of the MC3PHAC. The pin
numbers in the table refer to the 28-pin packages (see
Figure 1
).
Table 2. MC3PHAC Pin Descriptions (Sheet 1 of 3)
Pin
Number
Pin Name
Pin Function
1
V
REF
Reference voltage input for the on-chip ADC. For best signal-to-noise
performance, this pin should be tied to V
DDA
(analog).
2
RESET
A logic 0 on this pin forces the MC3PHAC to its initial startup state. All
PWM outputs are placed in a high-impedance mode. Reset is a
bidirectional pin, allowing a reset of the entire system. It is driven low
when an internal reset source is asserted (for example, loss of clock or
low V
DD
).
3
V
DDA
Provides power for the analog portions of the MC3PHAC, which include
the internal clock generation circuit (PLL) and the ADC
4
V
SSA
Returns power for the analog portions of the MC3PHAC, which include
the internal clock generation circuit (PLL) and the ADC
5
OSC2
Oscillator output used as part of a crystal or ceramic resonator clock
circuit.
(1)
6
OSC1
Oscillator input used as part of a crystal or ceramic resonator clock
circuit. Can also accept a signal from an external canned oscillator.
(1)
7
PLLCAP
A capacitor from this pin to ground affects the stability and reaction time
of the PLL clock circuit. Smaller values result in faster tracking of the
reference frequency. Larger values result in better stability. A value of
0.1
μ
F is typical.
8
PWMPOL_BASEFREQ
Input which is sampled at specific moments during initialization to
determine the PWM polarity and the base frequency (50 or 60 Hz)
9
PWM_U_TOP
PWM output signal for the top transistor driving motor phase U
10
PWM_U_BOT
PWM output signal for the bottom transistor driving motor phase U
11
PWM_V_TOP
PWM output signal for the top transistor driving motor phase V
12
PWM_V_BOT
PWM output signal for the bottom transistor driving motor phase V
13
PWM_W_TOP
PWM output signal for the top transistor driving motor phase W
14
PWM_W_BOT
PWM output signal for the bottom transistor driving motor phase W
F
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
.