COP8SA-DM National Semiconductor, COP8SA-DM Datasheet - Page 214

• Manufacturer Part Number: COP8SA-DM
• Description: MODULE DEBUGGING FOR COP8SA
• Manufacturer: National Semiconductor

Specifications of COP8SA-DM

• Module/board Type: Debugger Module
• For Use With/related Products: Cop 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *COP8SA-DM

Figure 4-9 shows the block diagram of a simple weight scale application. This
implementation of weight measurement may be used with the COP8SAx7 device which
has the Multi-input Wakeup feature. The pressure sensor circuit is based on a buffered
Wheatstone bridge arrangement. A current source and a capacitor generate the linear
ramp for the A/D conversion. A crystal oscillator is required for an accurate time base. A
50% duty cycle signal is generated for the audible tone. A 24-segment LCD display
indicates the weight to the user. Four switch inputs are used for configuring the scale.
4-22
COP8SAx7 APPLICATION IDEAS
USER SWITCHES
+
R
CRYSTAL OSCILLATOR
R+DR
R
R
Figure 4-10 Battery-powered Weight Measurement
A
Cref
SW1
+
Vcc
16-BIT TIMER
MULTI-INPUT
SOFTWARE
HALT MODE
PURPOSE
GENERAL
WAKEUP
CORE
TRAP
I/O
12
24 SEGMENT LCD DISPLAY
WITH 2-WAY MULTIPLEXING
BUZZER
Vcc
Vcc