EVB-EMC14XX SMSC, EVB-EMC14XX Datasheet - Page 7

• Manufacturer Part Number: EVB-EMC14XX
• Description: MCU, MPU & DSP Development Tools Evaluation Board
• Manufacturer: SMSC

Specifications of EVB-EMC14XX

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

EVB-EMC14XX User Manual
3 Hardware Description
3.1
3.2
3.3
3.3.1
3.4
3.5
3.6
3.7
SMSC EMC140X/2X
Introduction
EMC140X/2X Devices
USB to SMBus Bridge
Connecting to Remote Diodes
Resistance Error Correction (REC)
Power Source
Test Points
The EVB-EMC14XX provides the means to demonstrate all of the EMC140X/2X features and to view
and modify registers. LEDs indicate status information and test points are included to monitor system
voltages with a user provided voltmeter or oscilloscope.
A total of four of six SMSC devices are on-board the EVB-EMC14XX. Jumpers enable which version
is active on the EVB. Please contact SMSC for boards with the EMC1423 or EMC1424 devices.
The USB to SMBus bridge is based on an 8051 micro controller 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 USB and the SMBus. Power is sourced to the micro
controller from the USB interface for device power and communication.
Direct SMBus Connect Option
It is also possible to connect an external SMBus master to the EVB-EMC14XX. A few jumper settings
are all that is required to drive the any one of the devices on-board the EVB:
n
n
This EVB is populated with jumpers to connect to an external diode or CPU/GPU. If connecting to a
CPU’s thermal diode, it is necessary to provide a common ground. Also, it is usually necessary to bias
the appropriate CPU Vcc plane above this common ground to avoid forward-biasing the ESD diodes
with the temperature sensor signals. These connections have been provided on JP11 which is read by
EMC1422. Consult the CPU manufacturer’s datasheet for guidance on interfacing to the thermal diode.
Refer to the schematic EMC14XX_EVB_SCH-7092-A.pdf for details on the EVB header connections.
The remote diode DN signal path has a 100 ohm series resistor to demonstrate the EMC140X/2X’s
REC feature. See
This EVB requires only one USB connection to power the entire board. The USB-SMBus bridge
regulates the +5V USB power to +3.3V used by the EMC140X/2X and other EVB circuitry.
Test points are provided for:
n
n
n
n
Simply remove the jumpers on JP6 and connect the SMBus master to the SCL, SDA and ALERT
pins, as well as an external supply for +3.3V.
The +3.3V can be supplied by the SMBus bridge by leaving the +3.3V jumper in place and retaining
the USB connection.
Ground
+3.3V power
+5V_USB power
ALERT, THERM, and SYS_SHDN outputs
Table 3.3
for details on the REC jumper settings.
7
Revision 1.0 (12-14-06)