Dc electrical characteristics – Rainbow Electronics LM81 User Manual
Page 6
DC Electrical Characteristics
(Continued)
The following specifications apply for +2.8V
DC
≤
V
+
≤
+3.8V
DC
, R
S
= 500
Ω
, unless otherwise specified. Boldface limits apply
for T
A
= T
J
= T
MIN
to T
MAX
; all other limits T
A
= T
J
= 25˚C. (Note 8)
Symbol
Parameter
Conditions
Typical
Limits
LM81BIM
Limits
LM81CIM
Units
(Note 9)
(Note 10)
(Note 10)
(Limits)
DAC CHARACTERISTICS
Resolution
8
Bits
DAC Error
V
+
= 3.3V
±
5
±
62.5
±
10
±
125
±
5
±
62.5
% (max)
mV (max)
% (max)
mV (max)
DAC Error Temperature
Sensitivity
100
100
ppm/˚C (max)
DAC Error Power Supply
Sensitivity
0.5
0.725
% (max)
R
L
Output Load Resistance
V
O
= 1.25V
625
625
Ω
(min)
C
L
Output Load Capacitance
20
20
pF (max)
FAN RPM-TO-DIGITAL CONVERTER
Fan RPM Error
+25˚C
≤
T
A
≤
+75˚C
±
10
±
10
% (max)
−10˚C
≤
T
A
≤
+100˚C
±
15
±
15
% (max)
−40˚C
≤
T
A
≤
+125˚C
±
20
±
20
% (max)
Full-scale Count
255
255
(max)
FAN1 and FAN2 Nominal Input
RPM (See
Section 6.0)
Divisor = 1, Fan Count =
153 (Note 14)
8800
RPM
Divisor = 2, Fan Count =
153 (Note 14)
4400
RPM
Divisor = 3, Fan Count =
153 (Note 14)
2200
RPM
Divisor = 4, Fan Count =
153 (Note 14)
1100
RPM
Internal Clock Frequency
+25˚C
≤
T
A
≤
+75˚C
22.5
20.2
20.2
kHz (min)
24.8
24.8
kHz (max)
−10˚C
≤
T
A
≤
+100˚C
22.5
19.1
19.1
kHz (min)
25.9
25.9
kHz (max)
−40˚C
≤
T
A
≤
+125˚C
22.5
18
27
18
27
kHz (min)
kHz (max)
LM81
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