Everest CORE - Product Manual |
Application Guide
INGENIA | 08/01/2019
45
•
The RC filter makes a 1st order f
c
(-3dB)
≈
16 kHz, but having the bandwidth of U1, the circuit should work
fine with signals up to 5 kHz.
•
C5 is decoupling capacitor for U1.
•
U1 alone might have sufficient ESD protection.
Bill of materials
Designato
r
Part Number
Manufacture
r
Package
Value / Description
C1, C2, C4
C1005NP01H102J050B
A
TDK
0402
Ceramic capacitor, 1 nF, 50 V, NP0
C3, C5
GRM155R71C104KA88D Murata
0402
Ceramic capacitor, 100 nF, 16 V, X7R
R1, R3, R5
RMCF0402FT1K00
Stackpole
0402
Thick film resistor, 1 k
Ω
, 1 % tolerance, 1/16 W
R2, R4, R6
RMCF0402FT10K0
Stackpole
0402
Thick film resistor, 10 k
Ω
, 1 % tolerance, 1/16
W
U1
74LVC3G17DP,125
NXP
8-TSSOP
Non-inverting triple Schmitt trigger buffer, 24
mA output, 1.65 V to 5.5 V supply
Quadrature / Incremental Encoder
This circuit RS422/RS485 line receivers as hysteresis comparators. Line receivers perform very good in this kind of
circuits due to its its price, high speed response, common mode tolerance and built-in ESD protection. The negative
terminal is biased to 2.5 V for compatibility with single-ended encoders, while the positive terminal is pulled-up for
an extra robustness in front of a weak and noisy connection.