TSM917
6) The trip voltages and hysteresis band
should be verified as follows:
PC Board Layout and Power-Supply Bypassing
While power-supply bypass capacitors are not
typically required, it is always good engineering
practice to use 0.1uF bypass capacitors close to the
device’s power supply pins when the power supply
impedance is high, the power supply leads are long,
or there is excessive noise on the power supply
traces. To reduce stray capacitance, it is also good
engineering practice to make signal trace lengths as
short as possible. Also recommended are a ground
plane and surface mount resistors and capacitors.
For VIN rising: VTHR = VREF x R1 x [(1/R1)
+ (1 / R2) + (1 / R3)] = 3V
For VIN falling: VTHF = VTHR - (R1 x VCC/R2) =
2.9V
and Hysteresis Band = VTHR – VTHF = 100mV
Page 12
TSM917DS r1p0
RTFDS
TOUCHSTONE [ TOUCHSTONE SEMICONDUCTOR INC ]
