MAX6643LBBAEE+ Maxim Integrated Products, MAX6643LBBAEE+ Datasheet - Page 4

• Manufacturer Part Number: MAX6643LBBAEE+
• Description: IC CNTRLR FAN SPEED 16-QSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX6643LBBAEE+

• Function: Fan Control, Temp Monitor
• Topology: ADC, PWM Generator, Tach Counter
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 125°C, External Sensor
• Output Type: PWM
• Output Alarm: Yes
• Output Fan: Yes
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 16-QSOP
• Full Temp Accuracy: +/- 3.5 C, +/- 3 C
• Digital Output - Bus Interface: Serial (2-Wire)
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Automatic PWM Fan-Speed Controllers with
Overtemperature Output
4
MAX6643
_______________________________________________________________________________________
10, 11
1, 15
2, 3
—
—
4
5
6
7
8
9
MAX6644
10, 11
1, 15
PIN
2, 3
6, 8
—
—
—
4
5
7
9
MAX6645
3, 5
7, 8
—
—
—
—
—
1
2
4
6
DXP2, DXP1
TACHSET
FULLSPD
FULLSPD
FAN_IN2,
TH1, TH2
FANFAIL
FAN_IN1
TL2, TL1
NAME
GND
DXP
OT
High-Temperature Threshold Inputs. Connect to V
leave unconnected to select the upper fan-control trip
temperature (T
Low-Temperature Threshold Inputs. Connect to V
leave unconnected to select the lower fan-control trip
temperature (T
Fan-Fail Alarm Output. FANFAIL is an active-low, open-drain
output. If the FAN_IN_ detects a fan failure, the FANFAIL output
asserts low.
FAN_IN_ Control Input. TACHSET controls what type of fan-fail
condition is being detected. Connect TACHSET to V
or leave floating to set locked rotor, current sense, or
tachometer configurations (see Table 3).
Active-High Logic Input. When pulled high, the fan runs at
100% duty cycle.
Active-Low Logic Input. When pulled low, the fan runs at 100%
duty cycle.
Ground
C om b i ned C ur r ent S our ce and A/D P osi ti ve Inp ut for Rem ote
D i od e. C onnect to anod e of r em ote d i od e- connected
tem p er atur e- sensi ng tr ansi stor . C onnect to G N D i f no r em ote
d i od e i s used . P l ace a 2200p F cap aci tor b etw een D X P _ and
G N D for noi se fi l ter i ng .
Active-Low, Open-Drain Overtemperature Output. When OT
threshold is exceeded, OT pulls low.
Fan- S ense Inp ut. FAN _IN _ can b e confi g ur ed to m oni tor ei ther a
fan’ s l og i c- l evel l ocked - r otor outp ut, tachom eter outp ut, or sense-
r esi stor w avefor m to d etect fan fai l ur e. The M AX 6643’ s FAN _IN _
i np ut can m oni tor onl y tachom eter si g nal s. The M AX 6644 and the
M AX 6645 can m oni tor any one of the thr ee si g nal typ es as
confi g ur ed usi ng the TAC H S E T i np ut.
HIGH
LOW
), in 5°C increments. See Table 2.
), in 5°C increments. See Table 1.
FUNCTION
Pin Description
DD
DD
, GND, or
DD
, GND, or
, GND,