(for specific circuits check out the other pages)
You want to control
- 7segment displays
- alpha-numeric segmented displays
- bar graph segmented displays
- character lcd displays
- d'arsonval movements (meter movements, those small coiled instruments found eg in analog multimeters)
- air core instruments
- dc motors
- Planned for the future: Syncro driver.
...no problem, PHCC can do it.
PHCC features two kinds of ways of how to hook up outputs
- Digital Out Type A
- Digital Out Type B
- (plus a third one, using I2C, is also possible)
This is a unidirectional multidrop bus. Data flows only in one direction: from the PHCC motherboard to the DOA daughterboards, all connected daughterboards see the data at the same time. It is a synchronous two wire bus, one data and one clock line.
Each daughterboard has a 8bit long address, this means that with the current implementation, up to 256 daughterboards could theoretically be connected to DOA. Repeaters/signal conditioners should be used with longer cables and for every few daughterboards. The protocol is called AP2PP, Addressable PIC to PIC Protocol. AP2PP code for the receiving side (daugherboards) is available for several different PIC microcontrollers. The code and protocol is very simple. Bits are serially transmitted, LSB first. Data gets latched in at the positive (low-to-high) going transition of the clk.
This is a unidirectional daisy-chained shift-register based bus. The input of one stage connects to the output of the previous stage. Similar to SPI (tm), but without select lines for each shift register. Three wire interface, data, clock, and store.
Bits are clocked in MSB first. The clk and store latch on positive (low-to-high) going transition. Can be used with the following chips: (non-complete list):
- 74xx595 / 74xx596
- TPIC6C595 / TPIC6C596 (Texas Instruments or compatible)
- STPIC6C595 (from ST)
- STP08C596 (from ST)
- STP16C596 (from ST, 16bit)
- A6595 (Allegro or compatible)
- UCN 5821A / UCN 5822A (Allegro or compatible)
- UCN 5841A / UCN 5842A (Allegro or compatible)
- CD / CMOS 4094
- MAX4820 (a quick glance over the datasheet looks like this chip should work as well)
- MIC5821/22 (from Micrel)
- combination of ULN2803 or UCN2981 with 74x595 or CMOS 4094
- but the most adaptable way is to use the 74xx595 / 74xx596 in combination with transistors. You just pop in the transistor that provides the current drive and voltage capability you need. While this approach takes up more boardspace, it is certainly the most allround solution of the ones mentioned on this page. Also, matching transitors are often easier to find than some of the spceialty chips above. And probably cheaper.
|chip||Manufacturer||Technology||Channels||max Output Voltage||output current|
|continous, all channels on||cont., not all on||pulsed abs. max|
|Transistors/74HC||T595 several||CMOS/Bipolar/FET||8||depends on Transistor||depends on transistor|
Note: all Specs are usually at 25degC, Note that most of these parts are not pin-compatible with each other. Some values are guesswork. Always refer to the datasheets for the guaranteed values and more info.