General Description
The MAX6603 dual-channel, platinum RTD-to-voltage
signal conditioner excites and amplifies the signal from
two external 200Ω platinum-resistive temperature
devices (Pt RTD) to achieve high-voltage, level-filtered
signals for temperature measurements. The MAX6603
provides a direct ratiometric output voltage to simplify
the interface to microcontrollers with integrated analogto-digital converters (ADCs). External precision resistors and calibration processes are not needed. The
MAX6603 provides the necessary signal-conditioning
functions, including ratiometric excitation current,
amplification, buffered voltage outputs, diagnostic fault
detections, and input protection. The MAX6603 amplifies signals from two RTDs operating over the -40°C to
+1000°C temperature range and provides the temperature information as two independent analog voltages.
The MAX6603 features a ±6°C (max) accuracy over the
+400°C to +600°C temperature range.
The MAX6603 has overvoltage protection up to +16V
on RTD inputs, and ±5kV electrostatic discharge (ESD)
protection at RTD input pins for reliable operation
where RTD temperature-sensing probes are used. The
MAX6603 monitors the RTD for faults and asserts the
respective DG output low for fault conditions. The analog voltage outputs can be readily connected to a variety of microcontrollers.
The MAX6603 is available in a small, 10-pin TDFN-EP
package and operates over the -40°C to +125°C automotive temperature range from a single +3V to +5.5V
power supply.
Applications
Automotive Exhaust Temperature Monitoring
Engine Control Management to Meet EURO IV
Regulations
Braking Systems
Industrial Temperature Sensors
Food Transportation Monitoring Systems
Industrial Process Measurements
Features
♦ Amplifies Pt RTD Temperature Signals
♦ ±5kV ESD Protection on RTD Inputs
♦ +16V Overvoltage Fault Protection on RTD Inputs
♦ Low RTD Excitation Current Minimizes Self-
Heating Errors
♦ Small, 10-Pin TDFN Package
♦ Fully Ratiometric Operation
♦ No Calibration Required for Standard RTDs
♦ RTD Diagnostic Check
♦ High Accuracy: ±6°C (max) from +400°C to +600°C
MAX6603
Dual-Channel, Platinum
RTD-to-Voltage Signal Conditioner
________________________________________________________________ Maxim Integrated Products 1
1
3
4
10
+
8
7
OUT1
V
CC
RS2+
RS1+
MAX6603
29
OUT2RS2-
56
GNDRS1-
TDFN
3mm x 3mm x 0.8mm
TOP VIEW
DG2
DG1
Pin Configuration
Ordering Information
19-3975; Rev 0; 4/06
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
PART PIN-PACKAGE
PKG
CODE
MAX6603ATB+ 10 TDFN-EP*
T1033-1
EVALUATION KIT
AVAILABLE
Note: Device is specified over the -40°C to +125°C tempera-
ture range.
*EP = Exposed pad.
+Denotes lead-free package.
**Other base resistance values can be accommodated.
Contact the factory for more information.
RTD
200Ω**
MAX6603
Dual-Channel, Platinum RTD-to-Voltage
Signal Conditioner
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC= 3.0V to 5.5V, resistor connected between RS1+ and RS1- = 560Ω, resistor connected between RS2+ and RS2- = 560Ω,
T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at VCC= 5.0V, RL= 47kΩ between OUT_ and GND, TA= +25°C.)
(Note 1)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
(All voltages referenced to GND, unless otherwise noted.)
V
CC
........................................................................-0.3V to +6.0V
RS1+, RS1-, RS2+, RS2- .....................................-0.3V to +18.0V
OUT1, OUT2, DG1, DG2 ............................-0.3V to (V
CC
+ 0.3V)
Continuous Power Dissipation (T
A
= +70°C)
10-Pin TDFN Single-Layer Board
(derate 18.5 mW/°C above +70°C).........................1481.5mW
10-Pin TDFN Multilayer Board
(derate 24.4 mW/°C above +70°C).........................1951.2mW
ESD Protection (OUT1, OUT2, DG1, DG2,
Human Body Model) .....................................................> ±2kV
ESD Protection (RS1+, RS2+, RS1-, RS2-,
V
CC
, GND, Human Body Model) ..................................> ±5kV
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Voltage V
CC
3.0 5.5 V
Input Over Voltage V
RS
RS1+, RS1-, RS2+, RS2- 16 V
3.9 5.5
Supply Current I
CC
Sink current during overvoltage fault
mA
CURRENT SOURCES
Excitation Current I
EXC
(Note 2)
1.0
mA
Excitation-Current Temperature
Coefficient
TCI
EXC
(Note 2) -7
ppm/°C
Minimum RS_- Voltage V
RS_-
3.4 V
Maximum RS_+ Voltage V
RS_+
4.0 V
Supply Ratiometric I
RATIO
VCC = +3V to +5.5V 0.2
mA/V
MAXIMUM TEMPERATURE ERROR (Note 3)
+400°C to +600°C, VCC = 5.0V ±6
-40°C to +400°C, VCC = 5.0V ±8
+600°C to +1000°C, VCC = 5.0V ±12
+400°C to +600°C, VCC = 3.0V ±10
-40°C to +400°C, VCC = 3.0V
RTD
+600°C to +1000°C, VCC = 3.0V ±20
°C
V
= V
RS1+
RS1 -
= V
RS2+
= V
= +16V
RS2-
0.58
36.2 47.1
1.12
±13.3
MAX6603
Dual-Channel, Platinum RTD-to-Voltage
Signal Conditioner
_______________________________________________________________________________________ 3
Note 1: All parameters are tested at TA= +25°C. Specifications over temperature are guaranteed by design.
Note 2: RTD resistance range is 150Ω to 900Ω for constant excitation current.
Note 3: A typical 200Ω RTD: R(T) = R
O
[1 + AT + BT2] is referenced for probe temperature-probe resistance relation. The parame-
ters in this section are not tested and are for reference only.
Note 4: RTD resistance is tested only at R
RTD
= 200Ω, 560Ω, 845Ω. The range is guaranteed by design.
Note 5: Parameters are tested in special test mode.
ELECTRICAL CHARACTERISTICS (continued)
(VCC= 3.0V to 5.5V, resistor connected between RS1+ and RS1- = 560Ω, resistor connected between RS2+ and RS2- = 560Ω,
T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at VCC= 5.0V, RL= 47kΩ between OUT_ and GND, TA= +25°C.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAXIMUM INPUT RESISTANCE-TO-OUTPUT VOLTAGE ERROR
494Ω to 627Ω, VCC = 5.0V 19
200Ω to 494Ω, VCC = 5.0V 27
627Ω to 866Ω, VCC = 5.0V 33
494Ω to 627Ω, VCC = 3.0V 19
200Ω to 494Ω, VCC = 3.0V 27
RTD (Note 4)
627Ω to 866Ω, VCC = 3.0V 33
mV
ANALOG OUTPUTS (OUT1, OUT2)
Output-Voltage Low (Max) V
OL
RL = 47kΩ between OUT_ and V
CC
(Note 5)
0.1 V
Output-Voltage High (Min) V
OH
RL = 47kΩ between OUT_ and GND
(Note 5)
VCC -
0.1
V
V
OUT
= V
CC
22 mA
Short-Circuit Current I
SC
V
OUT
= GND 12 mA
Maximum Capacitive Load C
L
500 pF
Minimum Resistive Load R
L
Between OUT_ and GND 20 kΩ
DIAGNOSTIC OUTPUTS (DG1, DG2)
Output-Voltage Low V
OL
I
SOURCE
= 1mA 0.2 V
Output-Voltage High V
OH
I
SINK
= 1mA
V
CC
-
0.2
V
Minimum Resistance for RS+,
RS - Open
Ω
Maximum Resistance for RS+,
RS - Short
60 Ω
R
RS - OPEN
R
RS - SHORT
8000