TC650/TC651
Tiny Integrated Temperature Sensor & Brushless DC Fan
Controller with Overtemperature Alert
Features
• Integrated Temperature Sensing and Multi-speed
Fan Control
• Built-in Overtemperature Alert (T
OVER
)
• Temperature-proportional Fan Speed Control for
Acoustic Noise Reduction and Longer Fan Life
• Pulse Width Modulation (PWM) Output Drive for
Cost and Power Savings
• Solid-state Temperature Sensing
• ±1°C (typ.) Accuracy from 25°C to +70°C
• Operating Range: 2.8V – 5.5V
•
TC651
includes Automatic Fan Shutdown
• Low Operating Current: 50 µA (typ.)
General Description
The TC650/TC651 are integrated temperature sensors
and brushless DC fan speed controllers. The TC650/
TC651 measure the junction temperature and control
the speed of the fan based on that temperature, making
them especially suited for applications in modern
electronic equipment.
Temperature data is converted from the on-chip
thermal sensing element and translated into a
fractional fan speed from 40% to 100%. A temperature
selection guide in the data sheet is used to choose the
low and high temperature limits to control the fan. The
TC650/TC651 also include a single trip point over-
temperature alert (T
OVER
) that eliminates the need for
additional temperature sensors. In addition, the TC651
features an auto fan shutdown function for additional
power savings.
The TC650/TC651 are easy to use, require no software
overhead and are, therefore, the ideal choice for
implementing thermal management in a variety of
systems.
Applications
•
•
•
•
•
•
Thermal Protection For Personal Computers
Digital Set-Top Boxes
Notebook Computers
Data Communications
Power Supplies
Projectors
Package Type
8-Pin MSOP
V
DD
1
NC 2
SHDN 3
GND 4
8 PWM
Related Literature
• Application Note 771 (DS00771)
TC650
TC651
7 GND
6 T
OVER
5 NC
2004 Microchip Technology Inc.
DS21450C-page 1
TC650/TC651
Typical Application Circuit
PICmicro
®
Microcontroller
+5V V
DD
+12V
TC650
TC651
1 V
DD
2 NC
PWM 8
GND 7
T
OVER
6
NC 5
GND
C
SLOW
DC Fan
500 mA
SHDN
Control
3 SHDN
4 GND
GND
Overtemperature
Alert
DS21450C-page 2
2004 Microchip Technology Inc.
TC650/TC651
1.0
ELECTRICAL
CHARACTERISTICS
†
Notice:
Stresses above those listed under "Absolute Maxi-
mum 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 above those indicated
in the operation sections of the specifications is not implied.
Exposure to Absolute Maximum Rating conditions for
extended periods may affect device reliability.
Absolute Maximum Ratings†
Input Voltage (V
DD
to GND) ................................... +6V
Output Voltage (OUT to GND) ................................. 6V
Voltage On Any Pin ....... (GND – 0.3V) to (V
DD
+ 0.3V)
Operating Temperature Range ......... –40°C to +125°C
Storage Temperature ........................ –65°C to +150°C
DC CHARACTERISTICS
Electrical Specifications:
Unless otherwise specified, V
DD
= 2.8V to 5.5V, SHDN = V
DD
, T
A
= –40°C to +125°C.
Parameters
Supply Voltage
Supply Current
SHDN Input
SHDN Input High Threshold
SHDN Input Low Threshold
PWM Output
PWM Output Low Voltage
PWM Output High Voltage
PWM Rise Time
PWM Fall Time
PWM Frequency
Start-up Time
V
OL
V
OH
t
R
t
F
f
OUT
t
STARTUP
—
V
DD
– 0.5
—
—
10
—
—
—
10
10
15
32/f
OUT
0.3
—
—
—
—
—
V
V
µs
µs
Hz
sec
V
DD
Rises from GND
or SHDN Released
Temperature Accuracy
High Temperature Accuracy
T
H ACC
T
H
– 3
–1.0
–2.5
Auto-shutdown Hysteresis
T
OVER
Output
T
OVER
Output High Voltage
T
OVER
Output Low Voltage
Absolute Accuracy
Trip Point Hysteresis
Note 1:
V
HIGH
V
LOW
T
OVER ACC
T
OVER HYST
V
DD
– 0.5
—
—
—
—
—
T
H
+ 10
5
—
0.4
—
—
V
V
°C
°C
I
SOURCE
= 1.2 mA
I
SINK
= 2.5 mA
At Trip Point
T
HYST
—
T
H
—
—
(T
H
-T
L
)/5
T
H
+ 3
+1.0
+2.5
—
°C
°C
°C
°C
Note 1
(T
H
– T
L
)
≤
20°C
(T
H
– T
L
)
≥
20°C
TC651 Only
I
SINK
= 1 mA
I
SOURCE
= 5 mA
I
OH
= 5 mA, 1 nF from
PWM to GND
I
OL
= 1 mA, 1 nF from
PWM to GND
V
IH
V
IL
65
—
—
—
—
15
%V
DD
%V
DD
Sym
V
DD
I
DD
Min
2.8
—
Typ
—
50
Max
5.5
90
Units
V
µA
PWM, T
OVER
are open
Conditions
Temperature Range Accuracy (T
H –
T
L
)
ACC
Transition from 90% to 100% Duty Cycle.
2004 Microchip Technology Inc.
DS21450C-page 3
TC650/TC651
TEMPERATURE CHARACTERISTICS
Electrical Specifications:
Unless otherwise noted, V
DD
= 2.8V to 5.5V, SHDN = V
DD
, T
A
= -40°C to +125°C.
Parameters
Temperature Ranges
Specified Temperature Range
Maximum Junction Temperature
Storage Temperature Range
Package Thermal Resistances
Thermal Resistance, 8L-MSOP
θ
JA
—
206.3
—
°C/W
T
A
T
J
T
A
–40
—
–65
—
—
—
+125
+150
+150
°C
°C
°C
Sym
Min
Typ
Max
Units
Conditions
DS21450C-page 4
2004 Microchip Technology Inc.
TC650/TC651
2.0
Note:
TYPICAL PERFORMANCE CURVES
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
Note:
Unless otherwise indicated, V
DD
= 2.8V to 5.5V, SHDN = V
DD
, T
A
= –40°C to +125°C.
90
80
V
DD
=
5.6
3.0
2.5
60
Temp Accuracy (°C)
70
2.0
1.5
1.0
0.5
0.0
V
DD
= 5.6
V
DD
= 2.7
T
L
T
1
T
2
T
3
T
4
T
H
I
DD
(µA)
50
40
30
20
10
0
-50 -25
0
25
V
DD
= 2.7
50
75 100 125 150
TEMPERATURE (°C)
T
THRESHOLD
FIGURE 2-1:
I
DD
vs. Temperature.
FIGURE 2-4:
V
TH
.
1.0
0.9
0.8
Temperature Accuracy vs.
500
450
400
V
DD
- V
OH
(V)
350
V
DD
= 2.8V
V
DD
= 5.5V
V
OL
(mV)
0.7
0.6
0.5
0.4
0.3
0.2
300
250
200
150
100
50
0.0
T
A
= +25°C
0
1
2
3
4
5
6
7
8
9
10
V
DD
= 2.8V
V
DD
= 5.5V
0.1
0.0
T
A
= +25°C
0
2
4
6
8 10 12 14 16 18 20
I
SOURCE
(mA)
I
SINK
(mA)
FIGURE 2-2:
1.0
0.9
0.8
PWM, I
SINK
vs. V
OL
.
FIGURE 2-5:
(V
DD
– V
OH
).
PWM, I
SOURCE
vs.
V
DD
= 2.8V
V
DD
- V
OH
(V)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0
1
2
3
4
5
6
T
A
= +25°C
7
8
9
10
V
DD
= 5.5V
I
SOURCE
(mA)
FIGURE 2-3:
(V
DD
– V
OH
).
T
OVER
, I
SOURCE
vs.
2004 Microchip Technology Inc.
DS21450C-page 5
