Datasheet

DS_DIM3R3400_08142013 E-mail: [e-mail]
http://www.deltaww.com/dcdc
P12
I2C PROTOCOL:
Data_Pointer is write-only. It is written from the second
byte of any I2C WRITE message (the first byte is the 7
bit I2C Address and the R/W bit). Subsequent data
bytes in a WRITE message (3rd Byte and beyond) only
increment Data_Pointer.
Any READ message will return the value of the internal
register referenced by Data_Pointer and increments
Data_Pointer by one. For instance, if the master
acknowledges (AK), the next internal register referenced
by Data_Pointer will be returned and Data_Pointer will
be incremented by one. This process is repeated until
the master does not acknowledge (NACK) and issues a
STOP bit.
Data_Pointer is an 8bit value. It is initialized to 00h at
reset, and after reaching FFh, it will not overflow.
Writing to registers not defined in Table1 has no effect.
Reading from these undefined registers will return 00h.
In both cases Data_Pointer is incremented.
Example from the point of view of the I2C Master:
1) START transmission.
2) Send 52h (addresses unit for writing, given address
52h was selected as shown in Table 4).
3) Send 1Eh (loads 1Eh into Data_Pointer).
4) STOP transmission.
5) START next transmission.
6) Send 53h (addresses unit for reading).
7) Unit will respond with the value of Status Bits (register
1Eh as shown in Table 1).
8) ACK (Data_Pointer is automatically incremented to
1Fh).
9) Unit will respond with the value of HU_CAP (register
1Fh).
10) NACK.
11) Stop Transmission.
I2C ADDRESS STRUCTURE:
7 bit I2C Address + R/W bit
Four bits are fixed (0101), three bits (xyz) are variable,
and the least-significant bit is the read/write bit.
Table 3: I2C address structure.
I2CADRESS SELECTION:
The three bits (xyz) of the I2C Address are set with a
single external resistor from the I2C_ADR (pin10) to
LOGIC_GND (pin13). The 8 possible addresses are
shown in Table4 with the respective resistance values.
Table 4: I2C address selection