LM285MX-2.5/NOPB National Semiconductor, LM285MX-2.5/NOPB Datasheet - Page 9

• Manufacturer Part Number: LM285MX-2.5/NOPB
• Description: IC VOLT REF MICROPWR 2.5V 8SOIC
• Manufacturer: National Semiconductor

Specifications of LM285MX-2.5/NOPB

• Reference Type: Shunt
• Voltage - Output: 2.5V
• Tolerance: ±1.5%
• Temperature Coefficient: 150ppm/°C
• Number Of Channels: 1
• Current - Cathode: 20µA
• Current - Output: 20mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Fixed / Adjust / Prog: Precision
• Output Voltage (max): 2.5V
• Reference Voltage Accuracy (max): 1.5
• Load Regulation: 10mV
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: SOIC N
• Leaded Process Compatible: Yes
• Rohs Compliant: Yes
• Peak Reflow Compatible (260 C): Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -
• Current - Quiescent: -
• Lead Free Status / Rohs Status: Compliant
• Other names: LM285MX-2.5; LM285MX-2.5TR

Adjustment Procedure
1.
2.
Typical supply current 50 μA
Adjust TC ADJ pot until voltage across R1 equals Kelvin temperature multiplied by the thermocouple Seebeck coefficient.
Adjust zero ADJ pot until voltage across R2 equals the thermocouple Seebeck coefficient multiplied by 273.2.
Thermocouple
Micropower Thermocouple Cold Junction Compensator
Type
T
K
S
J
Improving Regulation of Adjstable Regulators
Seebeck
efficient
(
μ
52.3
42.8
40.8
Co-
V/°C)
6.4
63.4 150Ω
523 1.24k
432
412 953Ω
(Ω)
R1
9
(Ω)
R2
1k
Across R1
551907
Voltage
@25°C
15.60
12.77
12.17
1.908
(mV)
Across R2
551906
Voltage
14.32
11.78
11.17
1.766
(mV)
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