Datasheet

DS1626/DS1726
2 of 12
PIN DESCRIPTION
PIN NAME FUNCTION
1 DQ Data Input/Output Pin (Tri-State) for 3-Wire Serial Communication
2
CLK/CNV
Clock Input Pin for 3-Wire Serial Communication. Controls temperature
measurements when the DS1626/DS1726 is configured as a stand-alone thermostat.
3
RST
Reset Input Pin for 3-Wire Serial Communication
4 GND Ground Pin
5 T
COM
Thermostat Output Pin (Push-Pull) with Programmable Hysteresis
6 T
LOW
Thermostat Output Pin (Push-Pull) with T
L
Trip Point
7 T
HIGH
Thermostat Output Pin (Push-Pull) with T
H
Trip Point
8 V
DD
Supply Voltage. +2.7V to +5.5V input power pin.
Table 1. DS1626/DS1726 REGISTER SUMMARY
REGISTER NAME
(USER ACCESS)
SIZE
MEMORY
TYPE
REGISTER CONTENTS
AND POWER-UP/POR STATE
Temperature
(Read Only)
12 Bits SRAM
Measured Temperature (Two’s Complement)
Power-Up/POR State: -60ºC (1100 0100 0000)
T
H
(Read/Write)
12 Bits EEPROM
Upper Alarm Trip Point (Two’s Complement)
Power-Up/POR State: User Defined
Initial State from Factory: +15°C (0000 1111 0000)
T
L
(Read/Write)
12 Bits EEPROM
Lower Alarm Trip Point (Two’s Complement)
Power-Up/POR State: User Defined
Initial State from Factory: +10°C (0000 1010 0000)
Configuration
(Various Bits are
Read/Write and Read
Only—See Table 3)
1 Byte
SRAM and
EEPROM
Configuration and Status Information (Unsigned)
4MSbs = SRAM and 4LSbs = EEPROM
Power-Up/POR State: 1000XXXX (XXXX = User
Defined)
Figure 1. DS1626/DS1726 FUNCTIONAL DIAGRAM
T
COM
T
HIGH
T
LOW
T
H
REGISTER
DIGITAL
COMPARATOR/LOGIC
CONFIGURATION REGISTER AND CONTROL LOGIC
ADDRESS
and
I/O CONTROL
V
DD
CLK/
C
N
V
SD
A
R
ST
GND
TEMPERATURE SENSOR AND ΔΣ ADC
TEMPERATURE REGISTER
T
L
REGISTER