73S1217F-EB-LITE Maxim Integrated Products, 73S1217F-EB-LITE Datasheet - Page 21

• Manufacturer Part Number: 73S1217F-EB-LITE
• Description: BOARD EVAL 73S1217F CBL/DOC/CD
• Manufacturer: Maxim Integrated Products

Specifications of 73S1217F-EB-LITE

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

UG_1217F_046
4.5
This section provides recommendations on proper schematic design that will help in designing circuits
that are functional and compatible with the software library APIs.
4.5.1 Reset Circuit
The 73S1217F Evaluation Board Lite provides a reset pushbutton that can be used when prototyping and
debugging software. The RESET pin should be supported by the external components shown in
R8 should be around 10 Ω. The capacitor C27 should be 10 µF. R8 and C27 should be mounted as
close as possible to the IC.
C43 (1000 pF) is shown for EFT protection and is optional.
4.5.2 Oscillators
The 73S1217F has two oscillators (see
RTC (32 kHz). The system clock should use a 12 MHz crystal to provide the proper system clock rates
for the USB, serial and smart card interfaces. The system oscillator requires a 1 MΩ parallel resistor to
insure proper oscillator startup.
The RTC oscillator drives a standard 32.768 kHz watch crystal. Crystals of this type are accurate and do
not require a high current oscillator circuit. The oscillator in the 73S1217F has been designed specifically to
handle watch crystals and is compatible with their high impedance and limited power handling capability.
Rev. 1.2
Schematic Information
The 32 kHz oscillator does not require a parallel startup resistor.
Figure 13: External Components for RESET
3.3V
+
Figure 14: Oscillator Circuit
C27
10uF
R10
Figure
1
10k
RESET
S27
SW
6); one for the primary system clock and the other for an
1000pF
C43
2
R8
10
73S1217F Evaluation Board Lite User Guide
RESET
73S1217F
Figure
5.
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