MAX6625PMTT+T Maxim Integrated Products, MAX6625PMTT+T Datasheet - Page 12

• Manufacturer Part Number: MAX6625PMTT+T
• Description: IC TEMP SENSOR I2C 6-TDFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX6625PMTT+T

• Function: Temp Monitoring System (Sensor)
• Topology: ADC, Comparator, Register Bank
• Sensor Type: Internal
• Sensing Temperature: -55°C ~ 125°C
• Output Type: I²C™/SMBus™
• Output Alarm: Yes
• Output Fan: Yes
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: -55°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 6-TDFN Exposed Pad
• Full Temp Accuracy: +/- 1 C
• Digital Output - Bus Interface: Serial (I2C)
• Digital Output - Number Of Bits: 9 bit
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 55 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MAX6625PMTT+T; MAX6625PMTT+TTR

Figure 7. Fan Controller
9-Bit/12-Bit Temperature Sensors with
I
Example 1: If T
+80°C, and the fault queue depth is set to four, OT
does not assert until four consecutive conversions
exceed +100°C. If the temperature is then read through
the I
again when four consecutive conversions are less than
+80°C.
Example 2: If T
+80°C, and the fault queue depth is set to four, OT
does not assert until four consecutive conversions
exceed +100°C. If the T
to +120°C, OT deasserts and the IC looks for a new
T
The MAX6625/MAX6626 offer a low-power shutdown
mode. Enter shutdown mode by programming the shut-
down bit of the control register high. In shutdown, the
temperature register is set to 8000H and the ADC is
turned off, reducing the device current draw to 1µA
(typ). After coming out of shutdown, the temperature
register continues to read 8000H until the first conver-
sion result appears. The fault queue is held in reset
during shutdown.
The MAX6625/MAX6626 supply current is less than
1mA when the I
used to drive high-impedance loads, the devices dissi-
pate negligible power; therefore, the die temperature is
essentially the same as the package temperature. The
12
HIGH
2
C-Compatible Serial Interface in a SOT23
2
______________________________________________________________________________________
C-compatible interface, OT deasserts. OT asserts
fault.
2
HIGH
HIGH
C-compatible interface is active. When
MAX6625R
MAX6626R
+3V TO +5V
2
+V
is set to +100°C, T
is set to +100°C, T
S
6
Thermal Considerations
HIGH
OT
4
register is then changed
+12V
12V 300mA
FAN MOTOR
LOGIC LEVEL
MOSFET
LOW
LOW
Shutdown
is set to
is set to
key to accurate temperature monitoring is good thermal
contact between the MAX6625/MAX6626 package and
the monitored device or circuit. In some applications,
the 6-pin SOT23 package may be small enough to fit
underneath a socketed µP, allowing the device to moni-
tor the µP’s temperature directly. Heat flows in and out
of plastic packages primarily through the leads. Short,
wide copper traces leading to the temperature monitor
ensure that heat transfers quickly and reliably. The rise
in die temperature due to self-heating is given by the
following formula:
where P
MAX6626, and θ
The typical thermal resistance is +110°C/W for the 6-
pin SOT23 package. To limit the effects of self-heating,
minimize the output currents. For example, if the
MAX6625/MAX6626 sink 4mA with the maximum OT V
specification of 0.8V, an additional 3.2mW of power is
dissipated within the IC. This corresponds to a 0.35°C
rise in the die temperature.
Figure 7 shows the MAX6625/MAX6626 used as a tem-
perature-triggered fan controller. Figure 8 shows the
MAX6625/MAX6626 used as a thermostat to control a
heating element.
Figure 8. Simple Thermostat
MAX6625P
MAX6626P
D
+3V TO +5V
3
is the power dissipated by the MAX6625/
+V S
6
OT
JA
4k
is the package’s thermal resistance.
5
∆T
J
= P
D
✕
2N3904
θ
JA
RELAY
5VDC, 20mA
125VAC, 1A
Applications
HEATER
HEATER
SUPPLY
L