TS3004 Datasheet, PDF (10/11 Pages) Touchstone Semiconductor Inc – A 1.55V to 5.25V, 1.9uA, 3.3us to 233s Silicon Timer

TS3004
approximately 80µs. This is well above the required
minimum pulse width of 40µs.
Flashing Railroad Lights with the TS3004
With only three resistors and two off the shelf LEDs,
the TS3004 can be configured into a flashing railroad
lights circuit. With the input divider set to
FDIV2:0 = 101 and RSET= 3.24MΩ, the O T output
frequency is 1Hz. Refer to Figure 4. During the time
the output is HIGH, only the pull-down LED is on
while when the output is LOW, only the pull-up LED
is on. The supply voltage of the circuit is 5V.
Using the TS3004 and a Potentiometer to Dim an
LED
The TS3004 can be configured to dim an LED by
modulating the pulse width of the PWMOUT output.
With the input divider set to FDIV2:0 = 011 and
RSET= 2MΩ, the O T output frequency is
approximately 100Hz (or 10ms period). Refer to
Figure 5. The CPWM capacitor was calculated using
Equation 2 with a pulse width of 8.1ms. To reduce
the pulse width from 8.1ms and in turn, dim the LED,
a 1MΩ potentiometer is used. The potentiometer is
connected to the PWM_CNTRL pin in a voltage
divider configuration. The supply voltage of the circuit
is 5V.
Figure 4: Flashing Railroad Lights with the
TS3004
Figure 5: TS3004 Configured to Dim an LED with a
Potentiometer
.
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