3250
PROGRAMMABLE, CHOPPER-
STABILIZED, PRECISION,
HALL-EFFECT SWITCH
PROGRAMMING PROTOCOL
The A3250x operate point and A3251x release point are
programmed by serially addressing the device through the
supply terminal (pin1). After the correct operate/release
point is determined, the device programming bits are
selected and then a “lock” set to prevent any further
(accidental) programming.
Program Enable.
To program the device, a sequence of
pulses is used to activate/enable the addressing mode as
shown in figure 1. This sequence of a V
PP
pulse, at least
seven V
PH
pulses, and a V
PP
pulse with no supply interrup-
tions, is designed to prevent the device from being pro-
grammed accidentally (for example, as a result of noise on
the supply line).
V
PP
PROGRAM ENABLE
(AT LEAST 7 PULSES)
V
PH
V
PL
t
d(1)
0
Dwg. WH-013
t
d(1)
t
d(0)
Figure 1 — Program enable
PROGRAMMING PROTOCOL over operating temperature range.
Limits
Characteristic
Programming Voltage
Symbol
V
PL
V
PH
V
PP
Programming Current
Pulse Width
I
PP
t
d(0)
t
d(1)
t
dP
Pulse Rise Time
Pulse Fall Time
t
r
t
f
Max. supply current during programming
OFF time between bits
Enable, address, program, or lock bit ON time
Program pulse ON time
V
PL
to V
PH
or V
PP
V
PH
or V
PP
to V
PL
Description
Minimum voltage during programming
Min.
4.5
9.0
20
—
20
20
100
11
5.0
Typ.
5.0
10
23
250
—
—
300
—
—
Max.
5.5
11
25
—
—
—
—
—
—
Units
V
V
V
mA
µs
µs
µs
µs
µs
NOTE: Typical data is at T
A
= +25°C and is for design information only.
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SANKEN [ SANKEN ELECTRIC ]
