28138 Parallax Inc, 28138 Datasheet - Page 8

• Manufacturer Part Number: 28138
• Description: BOARD DEV PROFESSIONAL
• Manufacturer: Parallax Inc
• Series: BASIC Stamp®r
• Type: MCUr

Specifications of 28138

• Contents: Development Board
• Processor To Be Evaluated: SX28AC/DP
• Interface Type: RS-232
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: BASIC Stamp®, Javelin Stamp, and SX28AC/DP
• For Use With: 900-00014 - SERVO CONTROLLER PICO GWS130-28029 - KIT PARTS SMART SENSORS27957 - MANUAL USER FOR JAVELIN STAMP28138 - BOARD DEV PROFESSIONAL805-00006 - CABLE USB A TO MINI B27937 - MEMORY STICK DATALOGGER658-1021-5 - PROGRAMMER TEACLIPPER/STAMP30010 - BASIC STAMP LOGIC ANALYZER27220 - BOOK STAMPWORKS27330 - PROGRAMMER STACHE BASIC STAMP27218 - MANUAL BASIC STAMP VER 2.0
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Audio Amplifier (X7)
The onboard audio amplifier includes a filter circuit that is ideal for commands like SOUND (BS1 and
SX/B), FREQOUT (BS2-family and SX/B), and DTMFOUT (BS2-family). A jumper allows the use of an
external 8 Ω speaker when additional volume is required.
L293D Push-Pull Driver (X8)
The L293D push-pull driver allows the experimenter to control high-current devices like relays, solenoids
lamps and motors to the PDB. Its push-pull configuration (which means it can sink or source current on
its output pins) with active-high enable inputs makes it ideal for creating h-bridge motor driver circuits, or
for driving unipolar and bipolar stepper motors. Note that the output-high voltage must be supplied to the
V+ terminal.
When the enable inputs are high the outputs will follow the inputs, otherwise the outputs will be in a Hi-Z
state.
See the L293D documentation (available separately) for additional details on use and
configuration.
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© Parallax, Inc. • Professional Development Board (#28138) • 06/2005