ATMEL AT90USB User Manual

AT90USBKey

.............................................................................................

Hardware User Guide

Section 1

Introduction...........................................................................................1-3

1.1 Overview...................................................................................................1-3

1.2 AT90USBKey Featu r e s............................................................................1-4

Section 2

Using the AT90USBKey .......................................................................2-5

2.1 Overview...................................................................................................2-5

2.2 Power Supply............................................................................................2- 6

2.3 Reset.........................................................................................................2-8

2.4 On-board Resources.................................................................................2-9

2.5 In-System Programming.........................................................................2-13

2.6 Debugging...............................................................................................2-14

Section 3

Troubleshooting Guide.......................................................................3-15

Section 4

Technical Specifications.......... ......... ......... .......... ......... ......... .......... ...4-16

Section 5

Technical Support............................. ......... .......... ......... ......... .......... ...5-17

Section 6

Complete Schematics.......................................... ......... ......... .......... ...6-18

AT90USBKey Hardware User Guide User Guide 1

7627A–AVR–04/06

1.1 Overview

Section 1

Introduction

Congratulations on acquiring the AVR® AT90USBKey. This kit is designed to give
designers a qui ck start to develop code on th e A VR ® and for prot oty ping and testing of
new designs with the AT90USB microcontroller family.

This document describes the AT90USBKey dedicated to the AT90USB AVR
microcontroller. This board is des ig ned to al low an eas y ev alu ation of t he product using
demonstration software.

To increase its demonstrative capabilities, this stand alone board has numerous on­board resources: USB, joystick, data-flash and temperature sensor.

Figure 1-1 . AT90USBKey

AT90USBKey Hardware User Guide 1-3

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Introduction

1.2 AT90USBKey Features

The AT90USBKey provides the following features:



AT90USB QFN64



AVR Studio® software interface



USB software interface for Device Firmware Upgrade (DFU bootloader)



Power supply flagged by “VCC-ON” LED:



JTAG interface (connector not mounted):



Serial interfaces:



On-board resources:



On-board RESET button

(1)

(2)

– regulated 3.3V
– from an external battery connector (for reduced host or OTG operation)
– from the USB interface (USB device bus powered application)

– for on-chip ISP
– for on-chip debugging using JTAG ICE

– 1 USB full/low speed device/host/OTG interface

– 4+1-ways joystick
– 2 Bi-Color LEDs
– temperature sensor
– serial dataflash memories
– all microcontroller I/O ports access on 2x8pin headers (not mounted)



On-board HWB button to force bootloader section execution at reset.



System clock:

– 8 MHz crystal

Notes: 1. The AVRUSBKey is supported by AVR Studio®, version 4.12 or higher. For up-to-

date information on this and other AVR tool products, please consult our web site.
The most recent version of AVR Studio®, AVR tools and this User Guide can be
found in the AVR section of the Atmel web site, http://www.atmel.com.

2. ATMEL Flip®, In System Programming Version 3 or Higher shall be used for Device
Firmware Upgrade. Please consult Atmel web site to retrieve the latex version of Flip
and the DFU bootloader Hex file if needed.

1-4 AT90USBKey Hardware User Guide

7627A–AVR–04/06

2.1 Overview

Section 2

Using the AT90USBKey

This chapter describes the AVRUSBKey and all its resources.

Figure 2-1 . AT90USBKey Overvi ew

AT90USBKey Hardware User Guide 2-5

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Using the AT90USBKey

2.2 Power Supply

2.2.1 Power Supply Sources

USB powered When used as a US B devic e bus powered application, the AVRUSBKey can be direct ly

Battery powered The ex ternal battery connector should be used when the AT90USBKey is used as a

The on-board power supply circuitry allows two power supply configurations:



from USB connector



from battery connector

powered via the USB VBUS power supply line.

USB host. This mode allows the AT90USBKey to provide a 5V power supply from its
VBUS pin.

– Need of a female battery clip
– Input supply from 8 up to 15V DC (min. 100mA)

Figure 2-2 . P ower supply schematic

J8

2
1

MTA
Ext power supply

VBUS

D3

LL4148

D4
LL4148

D6

LL4148

5V

U4

2

IN

7

SHDN

3

GND

LP3982

U3out=1.25*(1+(R15+R18)/R19)

-

C16

4.7uF

220nF
C17

OUT
OUT

FAULT

CC

SET

VBAT

1
4
8
6
5

33nF
C15

1
2

U5

IN
GND

LM340

OUT

100k 1%

R19
124k 1%

3

100nF
C18

VCC3

VCC3

R15

R18100k 1%

2-6 AT90USBKey Hardware User Guide

7627A–AVR–04/06

2.2.2 VBUS Generator

Using the AT90USBKey

When using the AT90USB microcontroller in USB host mode, the AT90USBKey should
provide a 5V power supply over the VBUS pin of its USB mini AB connector.

A couple of transistors allows the UVCON pin of the AT90USB to control the VBUS
generation (See Figure 2-3). In this mode the AT90USBKey is powered by external
battery power supply source.

Figure 2-3 . VBUS generator schematic

FDV304P/FAI

UVCON

5V

R24

M1

10k

R25

Q1
BC847B

100k

-

C19

4.7uF

VBUS

2.2.3 “POWER-ON“ LED

The POWER-ON LED (“D1”) is always lit when power is applied to AVRUSBKey
regardless of the power supply source.

AT90USBKey Hardware User Guide 2-7

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