TS3001 Datasheet, PDF (9/10 Pages) Touchstone Semiconductor Inc – A 1V/1uA Easy-to-Use Resistor-Tuned Silicon Oscillator/Timer

Using a Potentiometer to Trim the TS3001’s
Output Frequency
By using a fixed resistor and a potentiometer, the
output frequency of the TS3001 can be trimmed as
shown in Figure 4. By selecting a fixed resistor R1
with a tolerance of 0.1% and a potentiometer P1 with
a 5% tolerance, the output frequency can be trimmed
to provide a ±2% trimming range. As shown in Figure
4, R1+P1 set the output frequency to 25.052kHz
when P1 = 0Ω and with P1 =200kΩ, the resulting
output frequency is 24.024kHz.
TS3001
Using Standard Resistors to Increase FOUT
Resolution
The TS3001 can be configured to provide a 0.1%
resolution on the output frequency as shown in
Figure 5. To do so, R1 can be set to approximately
10% of the value selected for R2. In addition, R2 and
R1 should be chosen with a 0.1% and 1% tolerance,
respectively. Since R2 is 90% of the total resistance,
it has the largest impact on the resolution of the
output frequency. With R1 = 91kΩ and R2 = 910kΩ,
the output frequency is 90kHz and with R1 = 400kΩ
and R2 = 4MΩ, the output frequency is 23kHz.
Figure 4: Using a Fixed Resistor and a
Potentiometer to Trim the T 3001’s
Output Frequency.
Figure 5: Setting the T 3001’s Output
Frequency to 0.1% Resolution using
Standard Resistors.
TS3001DS r1p0
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RTFDS