X79000 Datasheet, PDF (13/18 Pages) Intersil Corporation – NV DAC with Selectable Output Range and Memory

X79000, X79001, X79002
Table 1. Control Registers
Byte
Address
MSB
7
6
38h
Volatile or
Non-volatile
39h
Volatile or
Non-volatile
DAC11
DAC3
DAC10
DAC2
5
DAC9
DAC1
4
DAC8
3
DAC7
2
DAC6
1
DAC5
LSB
0
Register
Name
DAC4
MSBs of DAC
Register
DAC0
Reserved Reserved Reserved Reserved
LSBs of DAC
Register
3Ch
Non-Volatile
VH2
VH1
VH0
Full Scale Configuration
000: External VH reference
001: 605mV
010: 1.21V
011: 1.815V
100: 2.42V
101: 3.025V
110, 111: Reserved
VL2
VL1
VL0
Zero Level Configuration
000: External VL reference
001: 151mV
010: 605mV
011: 1.21V
100: 1.815V
101: 2.42V
110, 111: Reserved
Count8 Count10
Counter Configuration
(for Up/Down Operation)
00: 12 bits
01: 10 bits
10: 8 bits
11: Reserved
Configuration
Register
3Fh
Volatile
NVDAC Reserved Reserved Reserved Reserved Reserved Reserved Reserved
Bytes at addresses 3Ah, 3Bh, 3Dh, and 3Eh are reserved.
Non-Volatile
Write Enable
IDENTIFICATION AND MEMORY ADDRESS BYTES
The first byte sent to the X79000, following a falling edge
at the CS pin, is called the “Identification Byte”. The most
significant bit (ID7) is the function selector bit. The next
six bits (ID6-ID1) are the Device Address bits (AS5-AS0).
To communicate to the X79000, the value of bits AS[5:0]
must correspond to the logic levels at pins A5, A4, A3,
A2, A1, and A0 respectively. If one or more of the
address pins doesn’t exist in a particular device, then the
corresponding device address bits must be set to “0”.
The LSB (ID0) is the R/W bit. This bit defines the
operation to be performed on the device being
addressed. When the R/W bit is “1”, then a Read
operation is selected. A “0” selects a write operation.
If the value of the Device Address bits doesn’t match the
logic levels at the Address pins, then the Read or Write
operation is aborted.
ID7 ID6 ID5 ID4 ID3 ID2 ID1 _ID0
1 AS5 AS4 AS3 AS2 AS1 AS0 R/W
Device
Address
Read or
Write
Slave Address
Bit(s)
ID7
ID6-ID1
ID0
Description
Function Selector bit
Device Address
Read or Write Operation Select
The byte sent to the X79000, immediately following the
Identification byte, is called the Memory Address Byte.
The value of this byte is the location of the first byte to
be written to, or read from the X79000. Valid values for
this byte are from 00h to 3Fh. If the value of the
“Memory Address byte” is invalid, the Read or Write
operation is aborted.
13
FN8147.0
March 17, 2005