6.0 XNOR Test .................................................................................................................................................................................... 29
7.0 DC Parameters ............................................................................................................................................................................. 30
8.0 AC Specifications .......................................................................................................................................................................... 33
Appendix A: Data Sheet Revision History ........................................................................................................................................... 36
The Microchip Web Site ...................................................................................................................................................................... 37
Customer Change Notification Service ............................................................................................................................................... 37
Customer Support ............................................................................................................................................................................... 37
Product Identification System ............................................................................................................................................................. 38
2007 - 2016 Microchip Technology Inc.
DS000002248A-page 3
USB2502
1.0
INTRODUCTION
The Microchip 2-Port Hub is fully compliant with the USB 2.0 Specification and will attach to a USB host as a Full-Speed
Hub or as a Full-/High-Speed Hub. The 2-Port Hub supports Low-Speed, Full-Speed, and High-Speed (if operating as
a High-Speed Hub) downstream devices on all of the enabled downstream ports.
The Hub works with an external USB power distribution switch device to control V
BUS
switching to downstream ports,
and to limit current and sense over-current conditions.
All required resistors on the USB ports are integrated into the Hub. This includes all series termination resistors on D+
and D– pins and all required pull-down and pull-up resistors on D+ and D– pins. The over-current sense inputs for the
downstream facing ports have internal pull-up resistors.
Throughout this document the upstream facing port of the hub will be referred to as the upstream port, and the down-
stream facing ports will be called the downstream ports.
1.1
OEM Selectable Features
A default configuration is available in the USB2502 following a reset. This configuration may be sufficient for some appli-
cations. Strapping option pins make it possible to modify a limited sub-set of the configuration options.
The USB2502 may also be configured by an external EEPROM or a microcontroller. When using the microcontroller
interface, the Hub appears as an SMBus slave device. If the Hub is pin-strapped for external EEPROM configuration
but no external EEPROM is present, then a value of ‘0’ will be written to all configuration data bit fields (the hub will
attach to the host with all ‘0’ values).
The 2-Port Hub supports several OEM selectable features:
• Operation as a Self-Powered USB Hub or as a Bus-Powered USB Hub.
• Operation as a Dynamic-Powered Hub (Hub operates as a Bus-Powered device if a local power source is not
available and switches to Self-Powered operation when a local power source is available).
• Optional OEM configuration via I
2
C EEPROM or via the industry standard SMBus interface from an external
SMBus Host.
• Compound device support (port is permanently hardwired to a downstream USB peripheral device).
• Hardware strapping options enable configuration of the following features.
- Non-Removable Ports
- Port Power Polarity (active high or active low logic)
招聘职位/职位要求A、Firmware/baseband EngineerPosition Requirements:1. Bachelor’s degree or above in Communications, Electronic or computer Engineering2. At least 4 years (for Bachelor degree) or 2 years (for ...
Dear friends in the smart home forum, I am not very talented. I have made many smart home solutions a long time ago, but they were shelved for various reasons. Today, I saw my friends' enthusiasm for ...
Provide fingerprint development kit (support delphi, vb, pb, java, linux) and u.are.u2000 fingerprint scanner, u.are.u4000 fingerprint scanner. You can visit our website to learn more http://www.cybio...
The best password: ppnn13%dkstFeb.1st The password means two lines of Du Mu's poem: She is more than thirteen years old, and she is in the prime of her youth. Second place: FLZX3000cY4yhx9day (The wat...
At present, the traffic congestion in cities is quite serious. According to relevant news reports: In China, the traffic congestion has expanded from megacities such as Beijing, Shanghai, and Guang...[Details]
All electronic design engineers and scientists have performed electrical signal analysis, or signal analysis for short. Through this basic measurement, they can gain insight into signal details and...[Details]
1 Introduction
As an emerging microfabrication technology, micro-electromechanical system (MEMS) technology has begun to be applied in various fields. It can integrate functions such as inform...[Details]
With the rapid development of urban economy, elevators are increasingly used as a vertical transportation tool. However, elevator fault detection and maintenance, especially the role of elevator remot...[Details]
Editor's note: In order to help technicians or engineers who have knowledge of PIC microcontroller assembly language quickly master the method of using C language to program PIC microcontrollers, t...[Details]
Instrument stepper motor
The stepper motor is an open-loop control element that converts electrical pulse signals into angular displacement or linear displacement. In the case of non...[Details]
1. Introduction
At present, most lighting equipment still uses traditional energy for lighting. Making full use of solar energy as the energy supply for lighting equipment is of great si...[Details]
Overview:
This paper introduces a method of connecting a CAN-bus network with Ethernet to form a medium-sized remote monitoring/data transmission network.
CAN (Controller Area Network) is ...[Details]
LED is the abbreviation of light emitting diode, which is an electric light source made of semiconductor technology. The core part of LED is a chip composed of P-type semiconductor and N-type semi...[Details]
Flooded Batteries
This battery developed in Germany can be used to power flashlights, strobe lights and toys as long as it is filled with water. This battery can be stored for 50 years and can...[Details]
Many battery-powered systems require a visual indicator to show when the battery needs to be replaced. LEDs are commonly used for this purpose, but they consume at least 10mA of current. This con...[Details]
Introduction
Liquid crystal, as a display device, is widely used in low-power products such as instruments, meters, and electronic equipment with its unique advantages. In the past, the displ...[Details]
It is well known to automotive suppliers that automakers are demanding more from their supply base. For connector suppliers, this means stricter requirements for product performance, stability and ...[Details]
The era of mobile access to the Internet has arrived, and it will rapidly change the business and infrastructure needs of mobile operators under a whole new trend of requirements. We need 4G LTE to...[Details]
Since AC mains power may experience power outages, voltage sags and surges, continuous undervoltage and overvoltage, and frequency fluctuations during supply, these factors will affect the continuous ...[Details]
Discrete Device
京公网安备 11010802033920号
EEWORLD
