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One Wire module Li'lBoard page.
Model number: LB6.09.
Description: Convert an RS-232-timed signal to the 1-wire® protocol.
Applications: Allow the use of 1-Wire (®Dallas, now Maxim) devices without having to deal too intimately with the unique bi-directional 1-Wire protocol.
Features:
•The polarity of the RS-232 line can be selected by installing a solder blob at SJ1 (to either pull up—typicaly used with UART-direct signals, or pull down—normal, Mark=Low RS232 signals) the IC's POL pin (apparently the device has an internal pull down on both the POL and the TXD pins).
• The 1-wire line is protected by two DS9503 devices (one can be omitted if higher programming voltages are not to be used on the 1-wire network).
• the R-C filtering as per Figure 10 in the DS2480B data sheet is provided. The 100 Ω resistor can be shorted out via SJ3.
Key components: DS2480B
Restrictions:
•Watch the stated requirement that Vdd must always be <= Vpp. Solder jumper SJ2 is provided to allow these two pins to be connected together or to allow the Vpp to be applied separately.
•Note that the names of the two RS232 pins are named with respect to the driving interface: RXD is the DS24980B's output and TXD is its input.
Images:
Click on image for full (PDF) schematic
Vin max: 5.5 V
Vin min: 4.5 V
SPI: No. (RS-232)
Tenth centers: YES