ESD Protection (All Pins, Human Body Model)...................±2kV
Operating Temperature Range ........................ -40NC to +125NC
Junction Temperature .....................................................+150NC
Storage Temperature Range .......................... -65NC to +150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) .....................................+260NC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional opera-
tion 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.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
TDFN
Junction-to-Ambient Thermal Resistance (B
JA
) ..........60NC/W
Junction-to-Case Thermal Resistance (B
JC
) ...............30NC/W
Note 1:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to
www.maximintegrated.com/thermal-tutorial.
DC ELECTRICAL CHARACTERISTICS
(T
A
= -40NC to +125NC, unless otherwise noted.) (Note 2)
PARAMETER
Supply Voltage
Pullup Supply Voltage
(Notes 3, 4)
Input Logic-Low
SYMBOL
V
DD
V
PU
V
IL
CONDITIONS
Local power (Note 3, 4)
Parasite power (Note 3)
Local power (Note 3)
(Notes 4, 6)
MIN
3.0
3.0
3.0
-0.3
TYP
3.3
MAX
3.7
3.7
V
DD
+0.8
lower
of 3.7V
or
(V
DD
+
0.3V)
lower
of 3.7V
or
(V
DD
+
0.3V)
280
900
5
-0.3
(Note 3)
I
BTC
T
A
= -40°C to +125°C, 100mV across
the thermocouple inputs (Note 3)
-1
-100
+1
+100
1000
1750
UNITS
V
V
V
Local power
Input Logic-High (Note 4)
V
IH
Parasite power
2.2
V
3.0
Output Sink Current
Standby Supply Current
Active Supply Current
DQ Input Current
Power-Supply Rejection
Input Leakage Current (AD0–AD3 Pins)
Thermocouple Input Bias Current
I
L
I
DDS
I
DD
I
DQ
V
I/O
= 0.4V (Note 4)
(Notes 7, 8)
V
DD
= 3.7V (Note 9)
(Note 10)
4.0
mA
nA
FA
FA
°C/V
FA
nA
Maxim Integrated
2
MAX31850/MAX31851
Cold-Junction Compensated, 1-Wire
Thermocouple-to-Digital Converters
THERMAL CHARACTERISTICS
(3.0V
P
V
DD
P
3.6V, T
A
= -40NC to +125NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
T
THERMOCOUPLE
= -100NC to +100NC,
T
A
= 0NC to +70NC (Note 12)
MAX31850K Thermocouple
Temperature Gain and Offset
Error (41.276FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -200NC to +700NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= +700NC to +1372NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -270NC to +1372NC,
T
A
= -40NC to +125NC (Note 12)
MAX31850J Thermocouple
Temperature Gain and Offset
Error (57.953FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -100NC to +100NC,
T
A
= 0NC to +70NC (Note 12)
T
THERMOCOUPLE
= -210NC to +750NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -210NC to +1200NC,
T
A
= -40NC to +125NC (Note 12)
T
THERMOCOUPLE
= -100NC to +100NC,
T
A
= 0NC to +70NC (Note 12)
MAX31850N Thermocouple
Temperature Gain and Offset
Error (36.256FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -200NC to +700NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= +700NC to +1300NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -270NC to +1300NC,
T
A
= -40NC to +125NC (Note 12)
MAX31850T Thermocouple
Temperature Gain and Offset
Error (52.18FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -100NC to +100NC,
T
A
= 0NC to +70NC (Note 12)
T
THERMOCOUPLE
= -270NC to +400NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -270NC to +400NC,
T
A
= -40NC to +125NC (Note 12)
T
THERMOCOUPLE
= -120NC to +100NC,
T
A
= -20NC to +85NC (Note 12)
MAX31850E Thermocouple
Temperature Gain and Offset
Error (76.373FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -200NC to +700NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= +700NC to +1000NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -270NC to +1000NC,
T
A
= -40NC to +125NC (Note 12)
MIN
-1
-2
-4
-6
-1
-2
-4
-1
-2
-4
-6
-1
-2
-4
-1
-2
-4
-5
TYP
MAX
+1
+2
NC
+4
+6
+1
+2
+4
+1
+2
NC
+4
+6
+1
+2
+4
+1
+2
NC
+4
+5
NC
NC
UNITS
Maxim Integrated
3
MAX31850/MAX31851
Cold-Junction Compensated, 1-Wire
Thermocouple-to-Digital Converters
THERMAL CHARACTERISTICS (continued)
(3.0V
P
V
DD
P
3.6V, T
A
= -40NC to +125NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
T
THERMOCOUPLE
= -50NC to +100NC,
T
A
= 0NC to +70NC (Note 12)
MAX31851R Thermocouple
Temperature Gain and Offset
Error (10.506FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -50NC to +700NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= +700NC to +1768NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -50NC to +1768NC,
T
A
= -40NC to +125NC (Note 12)
T
THERMOCOUPLE
= -50NC to +150NC,
T
A
= 0NC to +70NC (Note 12)
MAX31851S Thermocouple
Temperature Gain and Offset
Error (9.587FV/NC nominal
sensitivity) (Note 11)
T
THERMOCOUPLE
= -50NC to +700NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= +700NC to +1768NC,
T
A
= -20NC to +85NC (Note 12)
T
THERMOCOUPLE
= -50NC to +1768NC,
T
A
= -40NC to +125NC (Note 12)
Thermocouple Temperature Data
Resolution
Thermocouple Temperature Data
Long-Term Drift
Internal Cold-Junction
Temperature Error
Cold-Junction Temperature Data
Resolution
Temperature Conversion Time
(Thermocouple, Cold Junction,
Fault Detection)
t
CONV
Hot junction temperature = +400NC
T
A
= -40NC to +100NC (Note 13)
T
A
= -40NC to +125NC
(Note 14)
-2
0.0625
MIN
-2
-3
-5
-7
-2
-3
-5
-7
0.25
±0.24
+2
TYP
MAX
+2
+3
NC
+5
+7
+2
+3
NC
+5
+7
NC
NC
NC
NC
UNITS
72
100
ms
Maxim Integrated
4
MAX31850/MAX31851
Cold-Junction Compensated, 1-Wire
Thermocouple-to-Digital Converters
1-Wire TIMING CHARACTERISTICS
(3.0V
P
V
DD
P
3.6V, T
A
= -40NC to +125NC, unless otherwise noted.) (Notes 2, 3)
PARAMETER
Time to Strong Pullup On
Time Slot
Recovery Time
Write-0 Low Time
Write-1 Low Time
Read Data Valid
Reset Time High
Reset Time Low
Presence Detect High
Presence Detect Low
Capacitance: DQ
Capacitance: AD0–AD3
SYMBOL
t
SPON
t
SLOT
t
REC
t
LOW0
t
LOW1
t
RDV
t
RSTH
t
RSTL
t
PDHIGH
t
PDLOW
C
IN/OUT
C
IN_ADD
(Note 15)
(Note 15)
(Note 15)
(Note 15)
(Note 15)
(Note 15)
(Notes 15, 16)
(Note 15)
(Note 15)
(Note 17)
(Note 17)
480
480
15
60
60
240
25
50
CONDITIONS
Start Convert T command issued
60
1
60
1
120
15
15
MIN
TYP
MAX
8
120
UNITS
µs
µs
µs
µs
µs
µs
µs
µs
µs
µs
pF
pF
Note 2:
Limits are 100% production tested at T
A
= +25NC. Limits over the operating temperature range and relevant supply volt-
age range are guaranteed by design and characterization.
Note 3:
Limits are 100% production tested at T
A
= +25NC and +85NC. Limits over the operating temperature range and relevant sup-
ply voltage are guaranteed by design and characterization.
Note 4:
All voltages are referenced to GND. Currents entering the IC are specified positive and currents exiting the IC are negative.
Note 5:
The pullup supply voltage specification assumes that the pullup device is ideal, and therefore the high level of the pullup
is equal to V
PU
. To meet the device’s V
IH
specification, the actual supply rail for the strong pullup transistor must include
margin for the voltage drop across the transistor when it is turned on. Thus: V
PU_ACTUAL
= V
PU_IDEAL
+ V
TRANSISTOR
.
Note 6:
To guarantee a presence pulse under low-voltage parasite power conditions, V
ILMAX
, may have to be reduced to as low
as 0.5V.
Note 7:
Standby current specified up to +70NC.
Note 8:
To minimize I
DDS
, DQ should be within the following ranges: V
GND
P
V
DQ
P
V
GND
+ 0.3V or V
DD
- 0.3V
P
V
DQ
P
V
DD
.
Note 9:
Active current refers to supply current during active temperature conversions.
Note 10:
DQ is high (high-impedance state with external pullup).
Note 11:
Not including cold-junction temperature error or thermocouple nonlinearity.
Note 12:
Guaranteed by design. These limits represent six sigma distribution for T
A
= +25NC to +85NC. Outside this temperature
range, these limits are three sigma distribution.
Note 13:
Guaranteed by design. These limits represent a three sigma distribution.
Note 14:
After minimum V
DD
has been reached during power-up, wait 10ms before initiating temperature conversions.
Note 15:
See the
1-Wire Timing Diagrams.
Note 16:
Under parasite power, if t
RSTL
> 960Fs, a power-on reset (POR) may occur.
Note 17:
Represents the maximum capacitive load that may be applied to the pins and still maintain timing and logic state.