KSC1393OBU RF Transistor NPN Equivalent & Substitute Parts

Part Overview

The KSC1393OBU is an RF transistor NPN manufactured by onsemi, designed for RF applications operating at 700MHz with a maximum collector-emitter breakdown voltage of 30V and power dissipation of 250mW. The device is packaged in a through-hole TO-92-3 configuration and is classified as obsolete. Due to its obsolete status, equivalent and substitute parts from active manufacturers are necessary for new designs and ongoing production requirements. Substitute parts listed below maintain functional compatibility within specified electrical and mechanical parameters.

Key Parameters

Parameter	Value	Unit
Transistor Type	NPN	—
Voltage - Collector Emitter Breakdown (Max)	30V	V
Frequency - Transition	700MHz	MHz
Power - Max	250mW	mW
Current - Collector (Ic) (Max)	20mA	mA
DC Current Gain (hFE) (Min)	60 @ 2mA, 10V	—
Operating Temperature (TJ)	150°C	°C
Mounting Type	Through Hole	—
Package / Case	TO-92-3	—
Product Status	Obsolete	—

Substitute Part Grouping Explanation

Substitution of the KSC1393OBU is determined by the following critical parameters:

Electrical Compatibility Criteria:

Transistor Type: NPN configuration required
Voltage Rating: Collector-emitter breakdown voltage must equal or exceed 30V
Frequency Performance: Transition frequency must support 700MHz operation
Power Dissipation: Maximum power rating must accommodate 250mW
Current Capability: Collector current rating must support 20mA maximum
DC Current Gain: hFE minimum specification must meet or exceed 60

Mechanical Compatibility Criteria:

Mounting Type: Through-hole or surface-mount configurations
Package Type: TO-92-3 through-hole or equivalent surface-mount alternatives
Operating Temperature: Junction temperature rating of 150°C

The substitute parts listed below are grouped into two categories based on mounting technology: surface-mount alternatives from Infineon Technologies and Analog Devices Inc./Maxim Integrated. All substitute parts maintain NPN transistor type and 150°C operating temperature rating. Substitutes with higher voltage ratings, frequency capabilities, or power ratings provide enhanced performance margins for the 700MHz RF application.

Parameter Comparison

Parameter	KSC1393OBU (Main)	BFR35APE6327HTSA1	MAX2601ESA+T	BFP650H6327XTSA1	BFP182RE7764HTSA1	BFP420H6433XTMA1	BFP450H6433XTMA1	BFP640H6327XTSA1
Manufacturer	onsemi	Infineon	Analog Devices/Maxim	Infineon	Infineon	Infineon	Infineon	Infineon
Transistor Type	NPN	NPN	NPN	NPN	NPN	NPN	NPN	NPN
Voltage - Collector Emitter Breakdown (Max)	30V	15V	15V	4.5V	12V	5V	5V	4.5V
Frequency - Transition	700MHz	5GHz	1GHz	37GHz	8GHz	25GHz	24GHz	40GHz
Power - Max	250mW	280mW	6.4W	500mW	250mW	160mW	450mW	200mW
Current - Collector (Ic) (Max)	20mA	45mA	1.2A	150mA	35mA	35mA	100mA	50mA
DC Current Gain (hFE) (Min)	60 @ 2mA, 10V	70 @ 15mA, 8V	100 @ 250mA, 3V	110 @ 80mA, 3V	70 @ 10mA, 8V	60 @ 20mA, 4V	60 @ 50mA, 4V	110 @ 30mA, 3V
Operating Temperature (TJ)	150°C	150°C	150°C	150°C	150°C	150°C	150°C	150°C
Mounting Type	Through Hole	Surface Mount	Surface Mount	Surface Mount	Surface Mount	Surface Mount	Surface Mount	Surface Mount
Package / Case	TO-92-3	SOT-23-3	8-SOIC-EP	SOT-343	SOT-143R	SOT-343	SOT-343	SOT-343
Product Status	Obsolete	Active	Active	Active	Active	Active	Active	Active
RoHS Status	—	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant

Engineering Selection Recommendations

Product Status Consideration: The KSC1393OBU is classified as obsolete. All listed substitute parts are active products from established manufacturers (Infineon Technologies and Analog Devices Inc./Maxim Integrated), ensuring long-term availability and supply chain continuity.

Compliance and Certifications: All substitute parts are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements. The main part KSC1393OBU does not specify RoHS compliance status due to its obsolete classification.

Voltage Rating Selection:

BFR35APE6327HTSA1 and MAX2601ESA+T: Both rated at 15V, providing adequate margin below the 30V specification of the KSC1393OBU. Suitable for applications where voltage headroom is not critical.
BFP182RE7764HTSA1: Rated at 12V, lowest voltage rating among substitutes. Selection requires verification that application voltage does not exceed 12V.
BFP420H6433XTMA1, BFP450H6433XTMA1, BFP640H6327XTSA1, BFP650H6327XTSA1: All rated at 4.5V or 5V. These parts are suitable only for low-voltage RF applications and are not recommended for applications requiring the full 30V rating of the KSC1393OBU.

Frequency Performance: All substitute parts exceed the 700MHz transition frequency requirement of the KSC1393OBU. Selection based on frequency should consider application bandwidth requirements and potential impedance matching adjustments.

Power Dissipation:

MAX2601ESA+T: Rated at 6.4W, significantly exceeding the 250mW requirement. Suitable for high-power RF applications.
BFP650H6327XTSA1: Rated at 500mW, doubling the power capability of the KSC1393OBU.
BFP450H6433XTMA1: Rated at 450mW, providing enhanced power margin.
BFR35APE6327HTSA1: Rated at 280mW, closely matching the original specification.
BFP182RE7764HTSA1, BFP420H6433XTMA1, BFP640H6327XTSA1: Rated at 250mW, 160mW, and 200mW respectively, meeting or approaching the original power specification.

Mounting Technology: The KSC1393OBU uses through-hole TO-92-3 packaging. All substitute parts use surface-mount technology (SOT-23-3, SOT-143R, SOT-343, or 8-SOIC-EP). PCB redesign is required for any substitution.

Current Capability: All substitute parts meet or exceed the 20mA maximum collector current requirement of the KSC1393OBU.

Frequently Asked Questions (FAQ)

Q: Can the KSC1393OBU be directly replaced with a surface-mount substitute without circuit modification?

A: No. The KSC1393OBU is a through-hole TO-92-3 device, while all substitute parts are surface-mount components. PCB redesign is required to accommodate the different package footprints and pinout configurations. Additionally, circuit impedance matching and layout considerations may require adjustment for higher-frequency substitutes.

Q: Which substitute part is the closest electrical equivalent to the KSC1393OBU?

A: BFR35APE6327HTSA1 provides the closest electrical match, with a 15V voltage rating (exceeding the 30V requirement with adequate margin), 5GHz transition frequency (well above 700MHz), 280mW power rating (closely matching 250mW), and 70 hFE minimum gain (exceeding the 60 minimum requirement). This part is recommended for applications where voltage headroom and power dissipation are primary concerns.

Q: Can I use BFP650H6327XTSA1 as a substitute if my application operates at 5V or lower?

A: Yes, BFP650H6327XTSA1 is suitable for applications operating at 4.5V or lower. This part offers superior frequency performance (37GHz), higher power capability (500mW), and higher collector current rating (150mA). However, the 4.5V voltage rating limits its use to low-voltage RF circuits. Verify that your application voltage does not exceed 4.5V before selection.

Q: What is the difference between the SOT-343 and SOT-23-3 packages used in the substitute parts?

A: SOT-343 is a smaller surface-mount package (3 leads) compared to SOT-23-3 (also 3 leads but larger footprint). Both are surface-mount alternatives to the through-hole TO-92-3 package. SOT-343 is more compact and suitable for space-constrained applications, while SOT-23-3 offers slightly larger pad areas for easier hand soldering. Package selection depends on PCB layout requirements and manufacturing capabilities.

Q: Is MAX2601ESA+T suitable for 700MHz RF applications?

A: MAX2601ESA+T has a 1GHz transition frequency, which exceeds the 700MHz requirement. However, this part is designed for higher-power applications (6.4W maximum power dissipation) and operates at higher collector currents (1.2A maximum). It is suitable for 700MHz operation but is optimized for power amplifier applications rather than low-power RF circuits. Selection should be based on specific application power requirements.

Q: Do all substitute parts meet RoHS compliance requirements?

A: Yes. All substitute parts listed are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory standards. The original KSC1393OBU does not specify RoHS compliance due to its obsolete status.

Q: What is the impact of using a higher-frequency substitute part in a 700MHz application?

A: Higher-frequency substitutes (such as BFP640H6327XTSA1 at 40GHz or BFP650H6327XTSA1 at 37GHz) will operate reliably at 700MHz. However, circuit impedance matching, biasing networks, and PCB layout may require optimization to achieve equivalent performance. Parasitic effects become more significant at higher frequencies, potentially requiring adjustment of coupling capacitors, bias resistors, and transmission line characteristics.

Q: Can I use BFP182RE7764HTSA1 if my application requires 30V operation?

A: No. BFP182RE7764HTSA1 has a maximum collector-emitter breakdown voltage of 12V, which is insufficient for applications requiring 30V operation. Using this part in a 30V circuit will result in device failure. Select only substitute parts with voltage ratings equal to or exceeding your application requirements: BFR35APE6327HTSA1 (15V) or MAX2601ESA+T (15V) for 30V-compatible alternatives.

Q: What are the key parameters I should verify when selecting a substitute part?

A: Verify the following parameters in order of priority:

Voltage Rating: Ensure collector-emitter breakdown voltage meets or exceeds your application requirement (minimum 30V for KSC1393OBU replacement).
Frequency Performance: Confirm transition frequency supports your operating frequency (minimum 700MHz).
Power Dissipation: Verify maximum power rating accommodates your circuit power requirements (minimum 250mW).
Collector Current: Ensure maximum collector current rating supports your circuit current demands (minimum 20mA).
DC Current Gain: Confirm hFE minimum specification meets your biasing requirements (minimum 60).
Package Type: Verify PCB compatibility with the selected package (through-hole or surface-mount).
Product Status: Confirm active product status for long-term availability.