A1190 ALLEGRO [Allegro MicroSystems], A1190 Datasheet - Page 10

• Manufacturer Part Number: A1190
• Description: Programmable, Chopper-Stabilized, Two Wire Hall-Effect Switches
• Manufacturer: ALLEGRO [Allegro MicroSystems]

A1190, A1192,
and A1193
Code. The number used to identify the combination of fuses
activated in a bit field, expressed as the decimal equivalent of the
binary value. The LSB of a bit field is denoted as code 1, or bit 0.
Addressing. Setting the bit field code in a selected register by
serially applying a pulse train through the VCC pin of the device.
Each parameter can be measured during the addressing process,
but the internal fuses must be blown before the programming
code (and parameter value) becomes permanent.
Fuse Blowing. Applying a V
permanently set an addressed bit by blowing a fuse internal to the
device. Once a bit (fuse) has been blown, it cannot be reset.
Blow Pulse. A V
addressed fuse.
Cycling the Supply. Powering-down, and then powering-up the
supply voltage. Cycling the supply is used to clear the program-
ming settings in Try mode.
Table 2. Programming Logic Table
Key
0
1
7
0
7
B
B
Fuse Check
B
Programming Lock
OP
OP
OP
Register
Trim Up Counting
Trim Down Counting
Trim
PH
Name
pulse of sufficient duration to blow the
PH
pulse of sufficient duration to
Binary Format
[MSB → LSB]
000000
111111
111111
000000
000111
00 11 11
000000
111111
001000
Bit Field Address (Code)
Equivalent
Blow Mode
Try Mode
Decimal
Programmable, Chopper-Stabilized,
63
63
15
63
0
0
7
0
8
Programming Procedure
Programming involves selection of a register, a mode, and then
setting values for parameters in the register for evaluation or for
fuse blowing. Figure 10 provides an overview state diagram.
Register Selection Each programmable parameter can be
accessed through a specific register. To select a register, a
sequence of voltage pulses consisting of a V
V
must be applied serially to the VCC pin. The quantity of V
pulses is called the key, and uniquely identifies each register. The
pulses for selection of register key 1, is shown in figure 5. No
V
table 2.
Mode Selection After register selection, the mode is selected,
either Try or Blow mode. Try mode is selected by default. To
select Blow mode, that mode selection key must be sent.
PM
PM
pulses, and a V
pulse is sent for key 0. The register selections are shown in
Two Wire Hall-Effect Switches
Initial value (below minimum |B
starts with code 1); Code corresponds to bit field value (code
1 selects bit field value 000001)
Maximum selectable value (above maximum |B
Initial value (above maximum |B
starts with code 1); Code is automatically inverted (code 1
selects bit field value 111110)
Minimum selectable value (below minimum |B
Check integrity of all fuse bits versus low threshold
Check integrity of all fuse bits versus high threshold
Initial value (below minimum |B
of 1 bit per sequence)
Maximum selectable value (above maximum |B
allows selection of 1 bit per sequence)
Locks out access to all registers except Fuse Check
PH
pulse (with no V
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
Description
OP
OP
OP
CC
| ) (Try mode sequence
| ); (Only allows selection
| ) (Try mode sequence
supply interruptions)
PH
pulse, a series of
OP
OP
OP
|)
| )
| ); (Only
PM
10