DEMO9S08EL32 Freescale, DEMO9S08EL32 Datasheet - Page 8

• Manufacturer Part Number: DEMO9S08EL32
• Manufacturer: Freescale

Specifications of DEMO9S08EL32

• Lead Free Status / RoHS Status: Supplier Unconfirmed

D E M O 9 S 0 8 E L 3 2
U S E R
During application development, the board may be powered from either the USB-BDM or the
PWR connector. To utilize LIN functionality, however, the board must be powered from the
LIN bus or from PWR connector with an input voltage greater than +12VDC.
POWER SELECT
Power may be applied to the board through the integrated USB BDM circuitry, a 2.0mm barrel
connector, or through connector J1. Power selection is achieved using 2 selection headers:
PWR_SEL option header and the VX_EN option header.
PWR_SEL
The PWR_SEL option header selects power input either from the integrated USB BDM
circuitry or from the on-board voltage regulator. Figure 2 below details the PWR_SEL header
connections.
Figure 2: PWR_SEL Option Header
Power from the integrated BDM is drawn from the USB bus and is limited to 500 mA. This
current limit accounts for the total current supplied over the USB cable to the BDM circuit, the
target board, and any connected circuitry. Current drain in excess of 500 mA will violate the
USB specification and will cause the USB bus to disconnect. This will cause the board to
exhibit power cycling where the board appears to turn-on then off continually. Damage to the
host PC or the target board may also result.
The on-board voltage regulator (VR1) accepts power input through a 2.0mm barrel connector
(PWR). Input voltage may range from +6V to +18V. The voltage regulator (VR1) provides a
+5V fixed output limited to 250mA. Over-temperature and over-current limit built into the
voltage regulator provides protection from excessive stress. The user should consider the
maximum output current limit of VR1 when attempting to power off-board circuitry through
connector J1.
G U I D E
NOTE: Set PWR_SEL jumper to VB during application development. Use barrel connector
PWR_SEL
PWR_SEL
1
1
input (PWR) to support LIN functionality if needed.
2
2
3
3
Selects power input from USB-BDM
Selects power input from on-board regulator or J1
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A U G U S T
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