EVB-EMC1053 SMSC, EVB-EMC1053 Datasheet - Page 7

• Manufacturer Part Number: EVB-EMC1053
• Description: MCU, MPU & DSP Development Tools Evaluation Board
• Manufacturer: SMSC

Specifications of EVB-EMC1053

• Processor To Be Evaluated: EMC1053
• Interface Type: USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

EVB-EMC1043/1053/1063 User Manual
3 Circuit Description
3.1
3.2
3.3
3.4
3.5
3.6
3.7
SMSC EMC1043/1053/1063
Introduction
EMC1043/1053/1063
USB to SMBus Bridge
Remote Diode with Resistance Error Correction (R.E.C.)
Power Source
Direct SMBus Connect Option
Test Points
The EMC1043/1053/1063 EVB provides the means to demonstrate EMC1043/1053/1063 features and
to view and modify registers. LED Indicators and test points are included to show status information.
The EMC1043/1053/1063 is a family of SMBus temperature sensors with 1 internal and 2 external
sensors in an 8 pin MSOP package. Communications with the EMC1043/1053/1063 sensors is via the
SMBus.
The USB to SMBus bridge is based on an 8051 microcontroller with integrated USB and SMBus
interfaces as well as internal flash and RAM. During EVB manufacture, firmware is loaded into the
bridge that provides the interface between the SMBus and the USB driver. Power is sourced to the
MCU from the USB interface.
Two diode-connected 2N3904 transistors are mounted on the EVB, labeled Remote1 and Remote2.
The Remote2 diode DP signal path has a series resistor to demonstrate the EMC1043/1053/1063’s
R.E.C. feature. The resistor may be effectively removed from the circuit by installing a jumper on JP1.
See the Jumper Settings and Connection List for details on jumper settings.
This demo board derives +5V power from the USB port. The bridge microcontroller has an internal
voltage regulator that supplies +3.3V to the EMC1043/1053/1063 and other EVB circuits.
It is also possible to connect an external SMBus master to the EMC1043/1053/1063 EVB. A few
modifications to the circuit are required:
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Test points are provided for:
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Cut 3 traces connecting JP4 pins 3-4, 5-6 and 7-8 on the bottom side of the PCB. This will
disconnect the USB bridge from the SMBus. The pullup resistors for the SMBus SDA, and SCL
signals are also disconnected so external pullups will need to be supplied by the SMBus Master.
Install P1 or JP4 to provide an SMBus connector. See the Jumper Settings and Connection List
for details.
Optionally remove zero ohm resistor R31. When removed, the USB to SMBus bridge will not supply
+3.3V to the circuitry so power will need to be provided from an external source. If R31 is left
installed, power will be supplied from the USB connector when connected to a computer or USB
hub.
Ground
+3.3V power
+5V_USB power
7
Revision 1.1 (12-14-06)