Rainbow Electronics DS1857 - Manual (Page 8)

DS1857
Dual Temperature-Controlled Resistors with
External Temperature Input and Monitors
8 _____________________________________________________________________
DEVICE
ADDRESS
AD (AUXILIARY DEVICE ENABLE A0h)
MD (MAIN DEVICE ENABLE)
DEVICE ADDRESS
ADDRESS
ADDRESS
ADDRESS
R/W
R/W
DATA BUS
R/W
ADEN ADFIX
SDA
SCL
2-WIRE
INTERFACE
RHIZ
MON1
MON2
V CC
GND
WPEN
EEPROM
128 x 8 BIT
00h-7Fh
STANDARDS
PROT
AUX AD
ADDRESS
TABLE
SELECT
R/W
EEPROM
72 x 8 BIT
80h-C7h
TABLE 02
RESISTOR 0
LOOK-UP
TABLE
PROT
MAIN
MD
EEPROM
72 x 8 BIT
80h-C7h
SRAM
32 x 8 BIT
60h-7Fh
NOT PROTECTED
PROT
MAIN
MD
TEMP INDEX
ALARM FLAGS
MUX
CTRL
MEASUREMENT
ADDRESS
TABLE
SELECT
R/W
EEPROM
72 x 8 BIT
80h-C7h
TABLE 03
RESISTOR 1
LOOK-UP
TABLE
PROT
MAIN
MD
TEMP INDEX
V CC
R
RHIZ
R
WPEN
MONITORS LIMIT
HIGH
MONITORS LIMIT
LOW
TABLE SELECT
TEMP INDEX
MINT (BIT)
EXTTMP V
CC
MUX
A/D
12-BIT
A/D
CTRL
V
CC
V CC
PROT AUX
PROT MAIN
MPEN
APEN
COMPARATOR
MEASUREMENT
ALARM FLAGS
MONITORS LIMIT LOW
MONITORS LIMIT HIGH
COMP CTRL
INTERRUPT
MINT
TABLE 01
EEPROM
16 x 8 BIT
80h-8Fh
VENDOR
PROT
MAIN
MD R/W
DEVICE ADDRESS
ADDRESS
TABLE SELECT
MASKING (TMP, V
CC
, MON1, MON2)
ADFIX (BIT)
ADEN (BIT)
MPEN (BIT)
APEN (BIT)
INV2 (BIT)
INV1 (BIT)
RHIZ
RESISTOR 0
50k Ω FULL SCALE
256 POSITIONS
L0
H0
REGISTER
REGISTER
RHIZ
RESISTOR 1
50k Ω FULL SCALE
256 POSITIONS
L1
H1
A0
A1
A2
Figure 1. DS1857 Block Diagram