33970 Datasheet, PDF (32/36 Pages) Freescale Semiconductor, Inc – Dual Gauge Driver Integrated Circuit with Improved Damping Algorithms

TYPICAL APPLICATIONS
INTRODUCTION
Table 22. 33970 Setup, Configuration, and Usage Example (continued)
Step Command
Description
Reference Table
and or Figure
7
PECCR ^{(a) Check the Status of the RTZ by sending the null command to monitor SO bit RTZ0, RTZ1} Table 7 (page 14),
of Device Status SO
Table 15 (page 19)
- Bit PE12 is the null command
(b) Is RTZ0 (OD2) logic [0]? If not, Gauge 0 still returning and null command should be
resent.
8
RTZ
(a) Return the other gauge to the zero stop. If the second gauge is driving a different pointer _{Table 11 (page 16)}
than the first, a new RTZCR command may be required to change the Full Step time.
9
PECCR ^{(a) Check the Status of the RTZ by sending the null command to monitor SO, bit RTZ1 (OD3)} Table 7 (page 14),
- Bit PE12 is the null command
Table 15 (page 19)
(b) Is RTZ1 (OD3) logic [0]? If not, Gauge 1 still returning and null command should be
resent.
10
VELR
(a) Change the maximum velocity of the gauge
- Bits V8:V9 determine which gauge(s) will change the maximum velocity
Table 7 (page 15),
Table 21 (page 24)
- Bits V7:V0 determine the maximum velocity position from Table 21, Velocity Table
11
POS0R ^{(a) Position Gauge 0 pointer}
- Bits P011:P00: Desired Pointer Position
Table 9 (page 16),
Table 21 (page 24)
(b) Check SO for Out-of-Range V_PWR
- Bit OVUV (OD6) logic [1]? If so, use UV (OD8) and OV (OD9) to decide whether to
RTZ after valid V_PWR
(c) Check SO for overtemperature
- Bit OT0 logic [1]? If so, enable driver again. If OT0 continues to indicate
overtemperature, shut down Gauge 0
- If RTZ0 returns to normal, re-establish the zero reference by RTZ command
12
POS1R ^{(a) Position Gauge 1 pointer}
- Bits P1 11:P1 0: Desired Pointer Position
Table 10 (page 16),
Table 21 (page 24)
(b) Check SO for Out-of-Range V_PWR
- Bit OVUV logic [1]? If so, use UV (OD8) and OV (OD9) to decided whether to RTZ
after valid V_PWR
(c) Check SO for overtemperature
- Bit OT1 logic [1]? If so, enable driver again. If OT1 continues to indicate overtemperature,
shut down Gauge 1.
- If OT1 returns to normal, re-establish the zero reference by RTZ command
13
POS0R ^{(a) Return the pointers close to zero position using POS0R}
Table 9 (page 16)
(b) Move pointer position at least 12 microsteps CW to the nearest full step prior to RTZ
14
POS1R ^{(c) Return the pointers close to zero position using POS1R}
Table 10 (page 16)
(d) Move pointer position at least 12 microsteps CW to the nearest full step position prior to
RTZ
(e) Check SO to see if Gauge 0 has moved
- Bit MOV0 logic [1]? If so, Gauge 0 moved to the first microstep
Table 10 (page 16),
Table 15 (page 19)
33970
32
Analog Integrated Circuit Device Data
Freescale Semiconductor