ULQ2436M Allegro Micro Systems, Inc., ULQ2436M Datasheet - Page 3

• Manufacturer Part Number: ULQ2436M
• Description: Countdown Power Timer
• Manufacturer: Allegro Micro Systems, Inc.

OSC. An external resistor in the range of
200 k
in the range of 0.001 F to 1 F determine
the frequency of the internal oscillator. The
period of oscillation is nominally R
the overall output time period (after the
digital countdown) of
where t is in seconds. See also MODE
SELECT.
OUTPUT. The output is an open-collector
of a Darlington-connected transistor. The
output is ON (low) during the timing period.
An external Zener diode is used to protect
the output against inductive-load switching
transients and automotive “load dump”.
TOGGLE. A push-button, momentary-action
switch at this input toggles the timer from
the OFF to the ON state. The oscillator and
countdown circuitry are started on the rising
edge of the input pulse. Internal de-bounce
circuitry is included.
SUPPLY. The timer requires a supply current
applied to this pin through a current-limiting
resistor (R
shunt regulator provides a stable supply to
the device over wide supply voltage varia-
tions. Capacitor C
decoupling.
MODE SELECT. With MODE SELECT
connected to GROUND, the first activation
will run for the preset time delay. All activa-
tions after the first will time out at half of the
initial preset time. This sequence is reset
each time the supply is interrupted. With
MODE SELECT connected to SUPPLY
(V
delay each time it is activated.
2436
COUNTDOWN POWER TIMER
REG
), the timer will repeat the preset time
CIRCUIT DESCRIPTION
to 2 M
S
). An internal 8 volt Zener diode
t = 4064 R
and an external capacitor
S
is used to provide
T
C
T
T
C
T
with
detail specifications as may be required to permit improvements in the design of its products.
Components made under military approvals will be in accordance with the approval requirements.
MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other
rights of third parties which may result from its use.
COURTESY
Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the
The information included herein is believed to be accurate and reliable. However, Allegro
LIGHT
TO
BATTERY
COURTESY LIGHT TIMER
10 k
R
C
T
T
16 V
1
2
3
4
F/F
1 k
V REG
Dwg. No. ES-013
8
7
6
5
+
1 F