MAX1669 Datasheet, PDF (4/20 Pages) Maxim Integrated Products – Fan Controller and Remote Temperature Sensor with SMBus Serial Interface

Fan Controller and Remote Temperature Sensor
with SMBus Serial Interface
ELECTRICAL CHARACTERISTICS
(V_CC = +3.3V, T_A = -40°C to +85°C, unless otherwise noted.) (Note 5)
PARAMETER
CONDITIONS
MIN
ADC AND POWER SUPPLY
Temperature Resolution (Note 1)
Monotonicity guaranteed
8
Temperature Error, Remote Diode (Note 2) T_R = -55°C to +125°C, diode ideality factor = 1.013 -5
Supply Voltage Range
3
Average Operating Supply Current
Autoconvert mode, average measured over
1sec, FAN output set to 150Hz mode
Conversion Time
Conversion Rate
FAN OUTPUT
FAN Output Source Current
FAN Output Sink Current
FAN PWM Frequency Error
FAN Total Unadjusted Error
FAN Output Voltage High
From stop bit to conversion complete
47
Autoconvert mode
1.6
PWM mode, V_FAN forced to 2.9V
10
PWM mode, V_FAN forced to 0.4V
PWM mode, any setting
-25
DAC mode, any setting, R_L = 10kΩ to GND
-5
DAC mode, FAN duty factor = 1111b,
I_OUT = 5mA
2.94
FAN Output Voltage Low
SMBus INTERFACE
DAC mode, FAN duty factor = 0000b,
I_OUT = -5mA
Logic Input High Voltage
ADD_, I/O1, I/O2, SYNC, SMBCLK, SMBDATA;
V_CC = 3V to 5.5V
2.1
Logic Input Low Voltage
ADD_, I/O1, I/O2, SYNC, SMBCLK, SMBDATA;
V_CC = 3V to 5.5V
SMBDATA, ALERT, OVERT, I/O1, I/O2
Output Low Sink Current
Pin forced to 0.4V
6
ALERT, OVERT, I/O1, I/O2 Output
High Leakage Current
Pin forced to 5.5V
Logic Input Current
Logic inputs forced to V_CC or GND
-1
MAX UNITS
Bits
5
°C
5.5
V
100
µA
ms
2.4
Hz
mA
-10
mA
+25
%
5
%FS
V
0.2
V
V
0.8
V
mA
1
µA
1
µA
Note 1: Guaranteed but not 100% tested.
Note 2: T_R is the junction temperature of the remote diode. The temperature error specification is optimized to and guaranteed for a
diode-connected 2N3906 transistor with ideality factor = 1.013. Variations in the ideality factor “m” of the actual transistor
used will increase the temperature error by *. See the Temperature Error vs. Remote Diode Temperature graph in the
Typical Operating Characteristics for typical temperature errors using several random 2N3906s. See Remote Diode
Selection for remote diode forward-voltage requirements.
Note 3: The SMBus logic block is a static design that works with clock frequencies down to DC. While slow operation is possible, it
violates the 10kHz minimum clock frequency and SMBus specifications, and may monopolize the bus.
Note 4: Note that a transition must internally provide at least a hold time in order to bridge the undefined region (300ns max) of
SMBCLK’s falling edge.
Note 5: Specifications to -40°C are guaranteed by design and not production tested.
( ) ( ) ^*∆T
=
 1.013
 m
− 1^{}
273.15k + T_R
°C
4 _______________________________________________________________________________________