MCZ33976EG Freescale Semiconductor, MCZ33976EG Datasheet - Page 18

• Manufacturer Part Number: MCZ33976EG
• Description: IC DRIVER DUAL GAUGE SPI 24-SOIC
• Manufacturer: Freescale Semiconductor
• Type: Serial Peripheral Interface (SPI) Dual Step Motor Gauge Driverr

Specifications of MCZ33976EG

• Applications: Stepper Motor Driver, 2 Phase
• Number Of Outputs: 2
• Current - Output: 100mA
• Voltage - Supply: 6.5 V ~ 26 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-SOIC (7.5mm Width)
• Supply Current: 4 mA
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

0 is the indicator of an accumulator exceeding the decision
threshold of 0, and the pointer is assumed to still be moving.
Similarly, if the sign bit is logic [1] after a full step of
integration, the accumulator value is negative and the pointer
is assumed to be stopped. The integrator and accumulator
are initialized after each full step. If the PECCR command is
written to clock out the RTZ accumulator values via the SO,
the OD14 bit corresponds to the sign bit of the RTZ
accumulator.
preloaded accumulator for specific gauge, pointer, and full
step combinations. Bits RC10:RC5 are used to offset the
initial RTZ accumulator value, properly detecting a stalled
.
Table 12. RTZCR SI Register Assignment
The bits in
(D3:D0) and RC4 (D4), determine the full step time and,
therefore, the rate at which the pointer will move during an
RTZ event. The values of D12:D11 determine the multiplier
(M) used in equation (1) (refer to page 17).
preloaded into the RTZ integration accumulator to adjust the
detection threshold. Values range from -1 (00000000) to -
1009 (11111111) as shown in
000000.
(blanking (t)). The default value = 0
(D12:D11) and RC4 (D4), determine the time variables used
to calculate the full step times with equations (1) or (2)
illustrated above. RC3:RC0 determines the ∆t time. The ∆t
values range from 0 (0000) to 61.440 ms (1111) and are
shown in
calculate the full step time if RC3:RC0 = 0000. Use
equation (1) for all other combinations of RC3:RC0.
18
33976
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Read
Write
Bits
Accurate pointer stall detection depends on a correctly
RC12:RC11 (D12:D11) — These bits, along with RC3:RC0
RC12:RC11 = M; default value = 00
• 00 = 1
• 01 = 2
• 10 = 4
• 11 = 8 (Not to be used for design)
RC10:RC5 (D10:D5) — These bits determine the value
RC4 (D4) — This bit determines the RTZ blanking time
• 0 = 512 µs
• 1 = 768 µs
RC3:RC0 (D3:D0) — These bits, along with RC12:RC11
Note Equation (2) (refer to page 17) is only used to
RC12
Table
Table 12
D12
–
13. The default ∆t is 0 (0011).
are write-only.
RC11
D11
–
RC10
D10
–
Table
14, the default value =
RC9
D9
–
RC8
D8
–
RC7
D7
Address 101
–
RC6
D6
motor. The initial accumulator value at the start of a full step
of integration is negative. If the accumulator was correctly
preloaded, a free-moving pointer will result in a positive value
at the end of the integration time, and a stalled pointer will
result in a negative value. The preloaded values associated
with each combination of bits RC10:RC5 are illustrated in
Table
value resulting in an accumulator MSB to a logic [1] when the
motor is stalled. For the default mode, after a power-up or any
reset, the 33976 device sets the accumulator value to -1,
resulting in an unconditional RTZ pointer movement until it is
increased.
Table 13. RTZCR Full Step Time
–
RC3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
14, page 19. The accumulator should be loaded with a
RC5
D5
–
RC2
RC4
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
D4
–
Analog Integrated Circuit Device Data
RC3
D3
–
RC1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
Freescale Semiconductor
RC2
D2
–
RC0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
RC1
D1
–
∆t (ms)
12.288
16.384
20.480
24.576
28.672
32.768
36.864
40.960
45.056
49.152
53.248
57.344
61.440
4.096
8.192
RC0
0
D0
–