A1186 Allegro MicroSystems, A1186 Datasheet - Page 11

• Manufacturer Part Number: A1186
• Description: (A1185 / A1186) Unipolar Hall-Effect Switches
• Manufacturer: Allegro MicroSystems

The pulse sequences consist of the following groups of pulses:
1. An enable sequence.
2. A bitfield address sequence.
3. When permanently setting the bitfield, a long V
4. When permanently setting the bitfield, the level of V
Bitfields that are not set are evaluated as zeros. The bitfield-level
fuses for 0 value bitfields are never blown. This prevents inad-
A1185-DS, Rev. 1
ing pulse. (Note: Blown bit fuses cannot be reset.)
be allowed to drop to zero between each pulse sequence, in
order to clear all registers. However, when provisionally set-
ting bitfields, V
sequences, in order to maintain the prior bitfield settings while
preparing to set additional bitfields.
Ultrasensitive Two-Wire Field-Programmable Chopper-Stabilized Unipolar Hall Effect Switches
CC
must be maintained at V
V
V
V
V
V
V
PM
PH
PL
PM
PH
PL
0
0
V+
V+
Figure 5. Pulse sequence to provisionally try calibration value 5.
Figure 6. Pulse sequence to permanently encode calibration value 5 (101 binary, or
bitfield address 3 and bitfield address 1).
Enable
Enable
PL
between pulse
Try 5
Encode 00100
A1185 and A1186
PH
10
fuse-blow-
Address
Address
CC
2
must
(4
10
)
Blow
Monitoring
Optional
vertently setting the bitfield to 1. Instead, blowing the device-
level fuse protects the 0 bitfields from being accidentally set in
the future.
When provisionally trying the calibration value, one pulse
sequence is used, using decimal values. The sequence for setting
the value 5
When permanently setting values, the bitfields must be set indi-
vidually, and 5
set to 1 (000100
which is 1
sequences for permanently setting the calibration value 5 are
shown in figure 6. The final V
period, enough to blow the corresponding bitfield-level fuse.
Clear
t
10
Enable
10
). Bit 2 is ignored, and so remains 0.Two pulse
is shown in figure 5.
10
Encode 00001
2
, which is 4
must be programmed as binary 101. Bit 3 is
Address
2
Blow
(1
10
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
www.allegromicro.com
10
)
PH
), then bit 1 is set to 1 (000001
pulse is maintained for a longer
t
2
,
11