Typical applications, Recommended external components – Rainbow Electronics AT89C5122 User Manual

Page 17

Advertising
background image

17

AT8xC5122/23

4202E–SCR–06/06

Typical Applications

Recommended External components

All the external components described in the figure and table below must be imple-
mented as close as possible from the microcontroller package.

Table 3. External Components Bill Of Materials

Reference Description

Value

Comments

R1

USB Full Speed Pull-up

1.5 K

Ω

+/-10%

All product versions

R2

USB pad serial resistor

27

Ω

+/-10%

For AT8xC5122 versions

33

Ω

+/-10%

For AT83C5123 versions

R3

USB pad serial resistor

27

Ω

+/-10%

For AT8xC5122 versions

33

Ω

+/-10%

For AT83C5123 versions

R4

PLL filter resistor

1.8 K

Ω

+/-10%

All product versions

R5

CIO Pull-up resistor

10 K

Ω

+/10%

All product versions

C1

Power Supply filter capacitor

100 nF +80/-20%

All product versions

C2

PLL filter capacitor

33 pF +/-10%

All product versions

C3

PLL filter capacitor

150 pF +/-10%

All product versions

C4

USB pad decoupling capacitor

680 nF +/-30%

All product versions.

If USB interface is not used, this capacitor is optional

C5

Smart Card clock filter capacitor

27 pF +/-10%

All product versions.

C6

DC/DC Converter decoupling capacitor

10 µF +/-10%

Low ESR

All product versions.

This capacitor does not impact the USB Inrush Current

C7

DC/DC Converter filter capacitor

100 nF +80/-20%

All product versions

C8

Power Supply decoupling capacitor

4.7 µF +/-10%

All products versions

This capacitor impacts the USB Inrush Current. Maximum
application capacitance allowed by the USB standard is 10 µF.

C9

Power Supply filter capacitor

100 nF +80/-20C

All product versions

C10

Reset capacitor

10 µF +/-10%

Optional capacitor for all product versions

L1

DC/DC converter input inductance

10 µH +/- 10%

Min rated current : 200 mA

Min rated freq. : 4 MHz

All product versions.

Qualified component : Murata LQH32CN100K21L

If DC/DC converter is not used at 5V, this inductance is optional.

Q1

Crystal

8.0000 Mhz +/- 2500 ppm
max

ESR max : 100

Ω

All product versions

Advertising