Microchip Technology PAC1710, Руководство пользователя

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PAC17X0 HIGH-SIDE CURRENT
SENSORS EVALUATION
BOARD USER’S GUIDE

2015 Microchip Technology Inc. DS50002367A-page 23
Chapter 3. Hardware Description
3.1 INTRODUCTION
The PAC17X0 High-Side Current Sensors Evaluation Board provides the means to
evaluate features and to view and modify registers. There are two modes of evaluation
board current monitoring operation:
• Demo Mode: Monitors an on-board current source
• Sys Mode: Monitors an external current source
LEDs indicate status information and test points are included to monitor system
voltages with a user-provided voltmeter or oscilloscope.
3.1.1 PAC1710 and PAC1720
The PAC1710 and PAC1720 devices are SMBus-compliant, high-side, bidirectional
current-sense monitors in a 10-pin, 3 mm x 3 mm DFN package. Communications with
the sensor are via the SMBus. For details regarding the PAC1710 and PAC1720, refer
to the device data sheet.
3.1.2 Power Source
This evaluation board only requires a single USB cable to operate. USB bus voltage is
provided to the on-board test current sources and the USB-SMBus bridge. The
USB-SMBus bridge regulates the +5V USB power to +3.3V used by the PAC1710,
PAC1720 and other evaluation board circuitry.
3.2 USB-TO-SMBus BRIDGE
The communication bridge on the PAC17X0 evaluation board is based on the
MCP2221 protocol converter. The MCP2221 enables USB connectivity in applications
that have UART and/or I
2
C and SMBus interfaces.
The MCP2221 USB bridge requires a driver to be installed on the computer for proper
communication with the PAC17X0 devices. Please refer to
Section 2.1.1 “System
Requirements” to review the installation process of the MCP2221 communication driver.
3.2.1 Direct SMBus Connect Option
It is also possible to connect an external communication master to the PAC17X0:
• Remove the jumpers on J13 and connect the SMBus master to the SDA, SCL and
ALERT pins, as well as an external supply for +3.3V. Note that a return is also
provided on this header for convenience (GND).
• The +3.3V can be supplied by the communication bridge by leaving the +3.3V
jumper in place and retaining the USB connection.