The MAX3421E USB peripheral/host controller contains
he digital logic and analog circuitry necessary to
mplement a full-speed USB peripheral or a full-/low
speed host compliant to USB specification rev 2.0. A
built-in transceiver features ±15kV ESD protection and
programmable USB connect and disconnect. An inter
nal serial interface engine (SIE) handles low-level USB
protocol details such as error checking and bus retries
The MAX3421E operates using a register set accessed
by an SPI? interface that operates up to 26MHz. Any
SPI master (microprocessor, ASIC, DSP, etc.) can add
USB peripheral or host functionality using the simple 3
or 4-wire SPI interface.
The MAX3421E makes the vast collection of USB
peripherals available to any microprocessor, ASIC, o
DSP when it operates as a USB host. For point-to-poin
solutions, for example, a USB keyboard or mouse inter
aced to an embedded system, the firmware that oper
ates the MAX3421E can be simple since only a
argeted device is supported.
nternal level translators allow the SPI interface to run a
a system voltage between 1.4V and 3.6V. USB-timed
operations are done inside the MAX3421E with inter
upts provided at completion so an SPI master does no
need timers to meet USB timing requirements. The
MAX3421E includes eight general-purpose inputs and
outputs so any microprocessor that uses I/O pins to
mplement the SPI interface can reclaim the I/O pins
and gain additional ones.
The MAX3421E operates over the extended -40°C to
+85°C temperature range and is available in a 32-pin
TQFP package (5mm x 5mm) and a 32-pin TQFN pack
age (5mm x 5mm).