EL2125CS-T7 Equivalent & Substitute Parts

Part Overview

The EL2125CS-T7 is a voltage feedback amplifier integrated circuit manufactured by Renesas Electronics Corporation, housed in an 8-SOIC surface mount package. This device is classified as obsolete, indicating it is no longer in active production. The EL2125CS-T7 delivers a slew rate of 185V/µs with a -3dB bandwidth of 220 MHz, supporting supply voltages from 5V to 30V across an operating temperature range of -45°C to 85°C.

Due to its obsolete status, locating equivalent or substitute components is necessary for ongoing design support, production continuity, and system maintenance. Substitute parts must maintain functional compatibility through matching electrical characteristics and identical physical packaging specifications.

Key Parameters

Parameter	Value	Unit
Amplifier Type	Voltage Feedback	—
Number of Circuits	1	—
Slew Rate	185	V/µs
-3dB Bandwidth	220	MHz
Current - Input Bias	22	µA
Voltage - Input Offset	600	µV
Current - Supply	10.8	mA
Current - Output / Channel	250	mA
Voltage - Supply Span (Min)	5	V
Voltage - Supply Span (Max)	30	V
Operating Temperature	-45 to 85	°C
Package / Case	8-SOIC (0.154", 3.90mm Width)	—
Mounting Type	Surface Mount	—
RoHS Status	RoHS non-compliant	—

Substitute Part Grouping Explanation

Substitution of the EL2125CS-T7 is determined by strict adherence to the following electrical and mechanical parameters:

Primary Substitution Criteria:

Amplifier Type: Voltage Feedback (single circuit configuration)
Package / Case: 8-SOIC (0.154", 3.90mm Width)
Mounting Type: Surface Mount
Functional compatibility within specified electrical operating ranges

Secondary Compatibility Parameters:

Slew Rate: 185V/µs or greater
-3dB Bandwidth: 220 MHz or greater
Supply voltage range: Minimum 5V to Maximum 30V (or compatible subset)
Operating temperature range: Must encompass or match -45°C to 85°C
Current - Output / Channel: 250 mA or greater

Substitute parts identified in this reference maintain the 8-SOIC package form factor and voltage feedback amplifier topology. Variations in slew rate, bandwidth, and supply current reflect different design generations and manufacturers, but all listed substitutes operate within compatible electrical specifications for the intended application category.

Parameter Comparison

Parameter	EL2125CS-T7	LM7121IM/NOPB	LM7121IMX/NOPB	THS4031CD	THS4031CDR	THS4031ID	THS4031IDR
Manufacturer	Renesas	Texas Instruments	Texas Instruments	Texas Instruments	Texas Instruments	Texas Instruments	Texas Instruments
Amplifier Type	Voltage Feedback	Voltage Feedback	Voltage Feedback	Voltage Feedback	Voltage Feedback	Voltage Feedback	Voltage Feedback
Number of Circuits	1	1	1	1	1	1	1
Slew Rate (V/µs)	185	1300	1300	100	100	100	100
-3dB Bandwidth (MHz)	220	235	235	100	100	100	100
Current - Input Bias (µA)	22	5.2	5.2	3	3	3	3
Voltage - Input Offset (µV)	600	900	900	500	500	500	500
Current - Supply (mA)	10.8	5.3	5.3	8.5	8.5	8.5	8.5
Current - Output / Channel (mA)	250	71	71	90	90	90	90
Voltage - Supply Span Min (V)	5	4.5	4.5	9	9	9	9
Voltage - Supply Span Max (V)	30	33	33	32	32	32	32
Operating Temperature (°C)	-45 to 85	-40 to 85	-40 to 85	0 to 70	0 to 70	-40 to 85	-40 to 85
Package / Case	8-SOIC	8-SOIC	8-SOIC	8-SOIC	8-SOIC	8-SOIC	8-SOIC
Product Status	Obsolete	Active	Active	Last Time Buy	Obsolete	Last Time Buy	Active
RoHS Status	RoHS non-compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant

Engineering Selection Recommendations

Primary Recommendation: THS4031IDR

The THS4031IDR is the preferred substitute for the EL2125CS-T7. This device maintains active product status with 4,390 units in current inventory. It is ROHS3 compliant and carries REACH unaffected certification. The THS4031IDR operates across the extended temperature range of -40°C to 85°C, encompassing the original part's lower temperature limit of -45°C for most industrial applications. The 8-SOIC package form factor is identical to the EL2125CS-T7.

The THS4031IDR exhibits lower input bias current (3 µA versus 22 µA) and reduced input offset voltage (500 µV versus 600 µV), providing improved precision characteristics. While the slew rate (100V/µs) and bandwidth (100 MHz) are lower than the original part, these parameters remain suitable for voltage feedback amplifier applications within the specified supply voltage range of 9V to 32V.

Secondary Recommendation: LM7121IMX/NOPB

The LM7121IMX/NOPB offers enhanced performance characteristics with a slew rate of 1300V/µs and -3dB bandwidth of 235 MHz, exceeding the original EL2125CS-T7 specifications. This device is actively produced with 2,000 units in inventory and is ROHS3 compliant. The extended supply voltage range (4.5V to 33V) and operating temperature span (-40°C to 85°C) provide broad compatibility. Input bias current is significantly reduced to 5.2 µA. The primary limitation is the reduced output current capability (71 mA versus 250 mA), which may restrict applications requiring high output drive capability.

Tertiary Recommendation: LM7121IM/NOPB

The LM7121IM/NOPB shares identical electrical specifications with the LM7121IMX/NOPB variant, with 1,156 units available in inventory. The primary distinction is packaging format (Tube versus Cut Tape & Digi-Reel). Selection between these variants depends on procurement and assembly requirements.

Obsolete Status Alternatives: THS4031CD and THS4031CDR

The THS4031CD and THS4031CDR are classified as Last Time Buy and Obsolete respectively, with 1,814 and 1,572 units in inventory. These parts are suitable for legacy system support but are not recommended for new designs due to their end-of-life status. The THS4031CD operates within a restricted temperature range (0°C to 70°C), limiting applicability to extended temperature environments.

Frequently Asked Questions (FAQ)

Q: Can the LM7121IMX/NOPB directly replace the EL2125CS-T7 in all applications?

A: The LM7121IMX/NOPB is electrically compatible in the 8-SOIC package and maintains voltage feedback amplifier topology. However, the reduced output current capability (71 mA versus 250 mA) may limit applications requiring high output drive. Verify output current requirements in the specific circuit design before substitution.

Q: What is the significance of the different slew rates among substitute parts?

A: Slew rate determines the maximum rate of change of output voltage. The EL2125CS-T7 specifies 185V/µs, while the LM7121 series provides 1300V/µs and the THS4031 series provides 100V/µs. Higher slew rates enable faster signal transitions and reduced distortion in high-frequency applications. Lower slew rates may introduce signal degradation in bandwidth-limited designs. Application-specific frequency response requirements determine acceptable slew rate ranges.

Q: Why do some substitute parts have different minimum supply voltage specifications?

A: The EL2125CS-T7 operates from 5V minimum, while the THS4031 series requires 9V minimum. This reflects different internal circuit designs and biasing schemes. Designs operating at 5V to 8V supply voltages cannot use the THS4031 series without circuit modification. The LM7121 series, with 4.5V minimum, provides broader supply voltage compatibility.

Q: Is the 8-SOIC package identical across all listed parts?

A: Yes. All substitute parts utilize the 8-SOIC (0.154", 3.90mm Width) surface mount package. Physical dimensions, pin spacing, and PCB footprints are identical, enabling direct mechanical substitution without layout modifications.

Q: What does RoHS3 compliance mean for substitute part selection?

A: ROHS3 compliance indicates the part meets Restriction of Hazardous Substances Directive requirements, restricting lead, cadmium, mercury, and other hazardous materials. The original EL2125CS-T7 is RoHS non-compliant. Designs requiring RoHS compliance must select from the ROHS3-compliant substitute options: LM7121IM/NOPB, LM7121IMX/NOPB, THS4031CD, THS4031CDR, or THS4031IDR.

Q: How does product status affect long-term availability?

A: Active status (LM7121IMX/NOPB, THS4031IDR) indicates ongoing production and long-term availability. Last Time Buy status (THS4031CD, THS4031ID) indicates production is ending with a final purchase opportunity. Obsolete status (EL2125CS-T7, THS4031CDR) indicates production has ended. For new designs, select only Active status parts to ensure sustained component availability throughout the product lifecycle.

Q: Can the THS4031IDR operate at the EL2125CS-T7's minimum supply voltage of 5V?

A: No. The THS4031IDR requires a minimum supply voltage of 9V. Designs operating at 5V supply voltage cannot use the THS4031 series. The LM7121 series, with 4.5V minimum supply voltage, is compatible with 5V supply designs.

Q: What is the impact of input bias current differences on circuit design?

A: The EL2125CS-T7 specifies 22 µA input bias current, while substitute parts range from 3 µA to 5.2 µA. Lower input bias current reduces errors in high-impedance input circuits and minimizes offset voltage drift with temperature. Designs with high-impedance input sources benefit from the lower bias current of substitute parts. Standard impedance circuits are unaffected by this parameter variation.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message