BA09ST Linear Voltage Regulator IC Equivalent & Substitute Parts

Part Overview

The BA09ST is an active linear voltage regulator IC manufactured by Rohm Semiconductor, classified as a Power Management (PMIC) component. This positive fixed output regulator delivers 1A at 9V and is packaged in TO-220-5 Full Pack configuration for through-hole mounting applications. The device is designed for applications requiring stable 9V regulated output from input sources up to 25V. As an active product with full RoHS3 compliance and unlimited moisture sensitivity rating, the BA09ST remains in production. Equivalent and substitute parts are identified based on matching output voltage, output current capability, mounting type, and core protection features.

Substiute Parts

BA09ST

Rohm SemiconductorIn Stock: 1676BA09ST Datasheet

Current PartRFQ

BA90BC0WT

Rohm SemiconductorIn Stock: 1158BA90BC0WT Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the BA09ST is determined by the following critical parameters:

• Output voltage fixed at 9V
• Output current capability of 1A minimum
• Through-hole mounting in TO-220-5 package configuration
• Positive output configuration
• Single regulator output
• Over Current and Over Temperature protection as minimum requirements
• Active product status with current manufacturing support
• RoHS3 compliance

The BA90BC0WT qualifies as a direct substitute based on these criteria. Both devices share identical output voltage (9V), output current (1A), mounting type (Through Hole), package format (TO-220-5), and protection feature overlap (Over Current, Over Temperature). Both maintain active product status and RoHS3 compliance.

Parameter Comparison

Engineering Selection Recommendations

Both the BA09ST and BA90BC0WT are active products with full RoHS3 compliance and REACH unaffected status, making either suitable for new designs and production environments.

The BA09ST supports input voltages up to 25V and includes Over Voltage protection in addition to Over Current and Over Temperature protection. Select the BA09ST when input voltage sources may exceed 16V or when Over Voltage protection is a circuit requirement.

The BA90BC0WT operates with input voltages up to 16V and features lower quiescent current (0.5 mA versus 2.5 mA) and lower supply current (900 µA versus 5 mA). The extended operating temperature range (-40°C ~ 105°C versus -40°C ~ 85°C) provides additional thermal margin. Select the BA90BC0WT for applications with input voltages not exceeding 16V where reduced standby power consumption or extended temperature operation is beneficial.

Both devices are packaged identically in TO-220-5 Full Pack configuration and deliver 1A at 9V output, ensuring direct mechanical and electrical compatibility within the specified input voltage constraints.

Frequently Asked Questions (FAQ)

Q: Can BA90BC0WT replace BA09ST in all applications?

A: The BA90BC0WT is a direct substitute provided the input voltage does not exceed 16V. The BA09ST supports input voltages up to 25V. If your circuit supplies input voltage above 16V, the BA09ST must be used. If input voltage is limited to 16V or below, BA90BC0WT is compatible.

Q: What is the difference in quiescent current between these parts?

A: The BA09ST draws 2.5 mA quiescent current while the BA90BC0WT draws 0.5 mA. For battery-powered or low-power standby applications, the BA90BC0WT reduces idle power consumption by 80%.

Q: Are the packages identical?

A: Yes. Both the BA09ST and BA90BC0WT use TO-220-5 Full Pack configuration with through-hole mounting. PCB layouts and thermal management designs are directly compatible.

Q: Does the BA90BC0WT provide Over Voltage protection?

A: No. The BA90BC0WT includes Over Current and Over Temperature protection. The BA09ST adds Over Voltage protection. If Over Voltage protection is required by your circuit design, use the BA09ST.

Q: What is the temperature operating range difference?

A: The BA09ST operates from -40°C to 85°C. The BA90BC0WT extends to -40°C to 105°C, providing 20°C additional high-temperature margin. For applications in elevated ambient or high-power environments, the BA90BC0WT offers extended thermal headroom.

Q: Are both parts RoHS compliant?

A: Yes. Both BA09ST and BA90BC0WT are RoHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements for production and distribution.