KA431SAMFTF_G Equivalent & Substitute Parts

Part Overview

The KA431SAMFTF_G is a shunt voltage reference IC manufactured by onsemi, classified as a Power Management (PMIC) component. This adjustable reference provides a 2.495V output with ±1% tolerance and supports up to 100 mA output current in a SOT-23-3 flat lead package. The part is currently listed as obsolete, making equivalent and substitute parts essential for ongoing design support and production continuity.

Key Parameters

Parameter	Value
Manufacturer Part Number	KA431SAMFTF_G
Manufacturer	onsemi
Reference Type	Shunt
Output Type	Adjustable
Voltage - Output (Min/Fixed)	2.495V
Voltage - Output (Max)	36 V
Current - Output	100 mA
Tolerance	±1%
Temperature Coefficient	50ppm/°C Typical
Current - Cathode	1 mA
Operating Temperature	-25°C ~ 85°C (TA)
Package / Case	SOT-23-3 Flat Leads
Mounting Type	Surface Mount
Product Status	Obsolete

Substitute Part Grouping Explanation

Substitution of the KA431SAMFTF_G is determined by the following critical parameters:

Electrical Compatibility Requirements:

Reference type must be shunt
Output type must be adjustable
Voltage output range must encompass or match the 2.495V to 36V specification
Output current capability must be at least 100 mA
Tolerance must be ±1% or better
Temperature coefficient must be 50ppm/°C or lower
Cathode current must be 1 mA or compatible
Operating temperature range must cover -25°C to 85°C minimum

Mechanical Compatibility Requirements:

Package must be SOT-23-3 or equivalent footprint (TO-236-3, SC-59)
Mounting type must be surface mount
Pin configuration must be compatible with SOT-23-3 flat lead design

Substitute parts are grouped into three categories:

Parametric Equivalents - Identical electrical specifications with different packaging or product status (Active vs. Obsolete)
Similar Substitutes - Meet all critical electrical requirements with minor parameter variations (tolerance, temperature coefficient, output current)
Cross-Manufacturer Alternatives - Functionally equivalent parts from different manufacturers meeting the same electrical and mechanical criteria

Parameter Comparison

Part Number	Manufacturer	Voltage Output (Min)	Voltage Output (Max)	Output Current	Tolerance	Temp Coeff	Cathode Current	Temp Range	Package	Product Status
KA431SAMFTF_G	onsemi	2.495V	36V	100 mA	±1%	50ppm/°C	1 mA	-25°C ~ 85°C	SOT-23F-3	Obsolete
KA431SAMF2TF	onsemi	2.495V	36V	100 mA	±1%	50ppm/°C	1 mA	-25°C ~ 85°C	SOT-23F-3	Active
KA431SAMFTF	onsemi	2.495V	36V	100 mA	±1%	50ppm/°C	1 mA	-25°C ~ 85°C	SOT-23F-3	Active
LM431SBCMFX	onsemi	2.495V	36V	100 mA	±1%	50ppm/°C	1 mA	-25°C ~ 85°C	SOT-23F-3	Active
NCP432BCSNT1G	onsemi	2.5V	36V	40 µA	±0.5%	50ppm/°C	100 mA	0°C ~ 70°C	SOT-23-3	Active
NCP432BISNT1G	onsemi	2.5V	36V	40 µA	±0.5%	50ppm/°C	100 mA	-40°C ~ 85°C	SOT-23-3	Active
NCP432BVSNT1G	onsemi	2.5V	36V	40 µA	±0.5%	50ppm/°C	100 mA	-40°C ~ 125°C	SOT-23-3	Active
AN431AN-ATRE1	Diodes Incorporated	2.5V	36V	100 mA	±0.5%	20ppm/°C	1 mA	-40°C ~ 125°C	SOT-23-3	Active
AN431AN-ATRG1	Diodes Incorporated	2.5V	36V	100 mA	±0.5%	20ppm/°C	1 mA	-40°C ~ 125°C	SOT-23-3	Active
AN431BN-ATRE1	Diodes Incorporated	2.5V	36V	100 mA	±1%	20ppm/°C	1 mA	-40°C ~ 125°C	SOT-23-3	Active
AN431BN-ATRG1	Diodes Incorporated	2.5V	36V	100 mA	±1%	20ppm/°C	1 mA	-40°C ~ 125°C	SOT-23-3	Active

Engineering Selection Recommendations

Primary Recommendation - Parametric Equivalents:

The KA431SAMF2TF, KA431SAMFTF, and LM431SBCMFX are direct parametric equivalents with identical electrical specifications. All three are manufactured by onsemi, maintain the same voltage output range (2.495V to 36V), output current (100 mA), tolerance (±1%), and operating temperature range (-25°C to 85°C). These parts are currently in active product status with RoHS3 compliance and REACH unaffected certification. KA431SAMF2TF and KA431SAMFTF offer the highest inventory availability (194,100 and 40,015 units respectively).

Secondary Recommendation - Diodes Incorporated AN431 Series:

The AN431AN-ATRE1, AN431AN-ATRG1, AN431BN-ATRE1, and AN431BN-ATRG1 from Diodes Incorporated provide functional substitution with enhanced specifications. The AN431AN variants offer ±0.5% tolerance and 20ppm/°C temperature coefficient (superior to the original ±1% and 50ppm/°C). The AN431BN variants match the original ±1% tolerance while maintaining the improved 20ppm/°C temperature coefficient. All variants support the required 100 mA output current and operate across -40°C to 125°C, exceeding the original temperature range. These parts are RoHS3 compliant and REACH unaffected.

Alternative Consideration - onsemi NCP432 Series:

The NCP432BCSNT1G, NCP432BISNT1G, and NCP432BVSNT1G offer ±0.5% tolerance and improved temperature coefficient performance. However, these parts have reduced output current capability (40 µA vs. 100 mA) and inverted cathode current specifications (100 mA vs. 1 mA), making them suitable only for applications where lower output current is acceptable. NCP432BVSNT1G provides the widest operating temperature range (-40°C to 125°C).

All recommended substitutes maintain SOT-23-3 package compatibility, surface mount mounting type, and shunt reference architecture. Selection should be based on specific application requirements for output current, temperature range, and tolerance specifications.

Frequently Asked Questions (FAQ)

Q: Can I directly replace KA431SAMFTF_G with KA431SAMF2TF or KA431SAMFTF?

A: Yes. KA431SAMF2TF and KA431SAMFTF are parametric equivalents with identical electrical specifications (2.495V output, ±1% tolerance, 100 mA output current, 50ppm/°C temperature coefficient) and the same SOT-23-3 flat lead package. The primary difference is product status (Active vs. Obsolete) and packaging format (Tape & Reel vs. Cut Tape). Both are direct pin-compatible replacements.

Q: What is the difference between the onsemi KA431 and the Diodes Incorporated AN431 series?

A: Both are adjustable shunt voltage references with identical output voltage range (2.495V to 36V for KA431, 2.5V to 36V for AN431) and output current (100 mA). The AN431 series offers superior tolerance (±0.5% vs. ±1%) and lower temperature coefficient (20ppm/°C vs. 50ppm/°C). The AN431 also provides extended operating temperature range (-40°C to 125°C vs. -25°C to 85°C). Both use SOT-23-3 packaging and are pin-compatible.

Q: Why do the NCP432 parts show different cathode current specifications?

A: The NCP432 series has inverted current specifications compared to the KA431. The NCP432 specifies 40 µA output current and 100 mA cathode current, whereas the KA431 specifies 100 mA output current and 1 mA cathode current. This fundamental difference in circuit topology makes NCP432 unsuitable as a direct replacement for applications requiring 100 mA output current capability.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All recommended substitute parts (KA431SAMF2TF, KA431SAMFTF, LM431SBCMFX, AN431AN-ATRE1, AN431AN-ATRG1, AN431BN-ATRE1, AN431BN-ATRG1, NCP432BCSNT1G, NCP432BISNT1G, NCP432BVSNT1G) are RoHS3 compliant and REACH unaffected.

Q: What is the difference between SOT-23F-3 and SOT-23-3 packaging?

A: SOT-23F-3 denotes SOT-23-3 with flat leads, while SOT-23-3 refers to the standard package designation. Both are mechanically and electrically compatible in the TO-236-3 / SC-59 footprint. The "F" designation in SOT-23F-3 specifies the lead form but does not affect PCB compatibility or electrical performance.

Q: Which substitute offers the best temperature stability?

A: The Diodes Incorporated AN431 series (AN431AN-ATRE1, AN431AN-ATRG1, AN431BN-ATRE1, AN431BN-ATRG1) offers superior temperature stability with 20ppm/°C temperature coefficient compared to the original 50ppm/°C. This represents a 60% improvement in temperature coefficient performance.

Q: Can I use NCP432BVSNT1G for applications requiring -25°C to 85°C operation?

A: NCP432BVSNT1G operates across -40°C to 125°C, which encompasses the -25°C to 85°C range. However, the NCP432 series has fundamentally different current specifications (40 µA output vs. 100 mA output), making it unsuitable for applications requiring the original 100 mA output current capability regardless of temperature range.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message