COP8SA-DM National Semiconductor, COP8SA-DM Datasheet - Page 221

• 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

Because of its enhanced I/O structure, the COP8SAx7 can be used to directly drive up to
32 LED segments on the 28-pin device. The device features four high-current outputs
(L0-L3). Each output can sink at least 15 mA. The 32 LED segments can be driven in
multiplexed mode by connecting the L0-L3 lines to the common cathode of the eight-
segment LED display. Eight additional outputs are connected to the anodes to select the
specific LED segment. The 40/44 pin devices can drive up to 64 LED segments.
Brightness can be improved by reducing the number of muxed lines to three. This still
allows users to drive 24 segments, enough for most applications in the appliance market.
The core timer (T1) can be used to refresh the display. An external R/C clock generating
an interrupt, or the 50/60-Hz frequency of the main power supply, can also be used to
refresh the display.
In addition to the pins used for the display drive, additional I/O pins are available for
application-specific I/Os. These pins can also be used in conjunction with MICROWIRE/
PLUS peripherals, including A/D converters, zero cross detectors with built-in
comparator, and serial EEPROM.
4.11.1 Improved Brightness
Another way to improve the brightness of the LED display is to use one additional
transistor per muxed line. The muxed line can be any output of the controller, which frees
the L0-L3 lines for other purposes (LED drive, triac drive, etc.).
V
CC
V
Figure 4-15 LED Direct Drive Using COP8SAx7
CK1
CK0
GND
CC
COP8SAX7
RESET
D0
D1
D2
D3
L1
L2
L3
L3
L0
L2
L1
L0
8 X R
V
CC
8 X R
HDN11070
3,8
COP8SAx7 APPLICATION IDEAS
HDN11070
3,8
HDN11070
3,8
HDN11070
3,8
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