Rainbow Electronics DS1780 - Manual

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FEATURES
Direct-to-digital temperature sensor requires
no external components or user calibration
Two fan speed sensors
Monitors 6 power supply voltages
8-bit DAC for fan speed control
Intrusion detect for security (detects when
chassis lid has been removed, even if power is
off)
Remote system reset
System interrupt availability on all monitored
functions (temperature, voltages, fan speed,
chassis intrusion)
2-wire interface with 2-bit addressability
Integrated NAND TREE for board level
testability
Wide power supply range (2.8V ≤ V
DD
≤
5.75V)
High integration in a small 24-pin 173-mil
TSSOP
Applications include monitoring of personal
computers or any microprocessor-based
system
PIN ASSIGNMENT
PIN DESCRIPTION
A0/NT
OUT
- Address Input / NAND
TREE Output
A1 - Address Input
SDA - 2-Wire Serial Data
Input/Output
SCL - 2-Wire Serial Clock
FANx - Tachometer Inputs
CHS - Chassis Intrusion Detector
Input
GNDD - Digital Ground
V
DD
- Power Supply Voltage (2.8V
to 5.75V)
INT - Hardware Interrupt output
V
OUT
/NT
IN
- DAC output / NAND TREE
Input
RST - Remote System Reset
GNDA - Analog Ground
+xxV
IN
- Positive Voltage Inputs
+2.5V
S
/+V
CCP2
- Positive/negative Voltage
Input
VIDx - Processor Voltage Supply
Readout Inputs
DS1780
CPU Peripheral Monitor
www.dalsemi.com
DS1780E
24-Pin TSSOP (173-mil)
23
VID0
VID
VID2
VID3
VID4
+V
CCP1
+2.5 V
IN
+3.3 V
IN
+5 V
IN
+12 V
IN
+2.5 V
S
/+V
CCP2
GNDA
1
2
3
4
5
6
7
8
9
10
11
12 24
22
21
20
19
18
17
16
15
14
13 SDA
FAN1
CHS
GNDD
V
DD
INT
V
OUT
/NT
IN
RST
A1
SCL
FAN2
A0/NT
OUT