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onsemi KSD1691GSTU
- Part No.:
- KSD1691GSTU
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-225AA, TO-126-3
- Datasheet:
-
KSD1691GSTU.pdf
- Description:
- TRANS NPN 60V 5A TO-126-3
- Quantity:
- Payment:
- Shipping:
Inventory:367
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Product details
Overview
KSD1691GSTU from onsemi is an NPN epitaxial silicon power transistor in TO-126-3LD package, rated for 60 V VCEO, 5 A DC collector current, and 1.3 W power dissipation at TA = 25 °C. It delivers low VCE(sat) (0.1–0.3 V at IC = 2 A, IB = 0.2 A) and high hFE up to 400, enabling efficient switching in DC motor drivers and relay drivers.
For engineers reviewing the KSD1691GSTU datasheet, pinout, applications, or equivalent options, key selection criteria include verified saturation voltage under pulsed load, hFE grade G classification (200–400), thermal derating above 25 °C, and complementary pairing with KSB1151 for push-pull output stages.
Technical Context
This device operates as a medium-power NPN bipolar junction transistor optimized for linear and switching applications where low saturation voltage and high current gain are critical. Its safe operating area (SOA) supports pulse currents up to 8 A (PW ≤ 10 ms, duty ≤ 50%) and DC operation up to 5 A with proper heatsinking.
The KSD1691GSTU features graded hFE bins (G = 200–400), defined at VCE = 1 V and IC = 2 A, and exhibits turn-on time of 0.2–1 µs and storage time of 1.1–2.5 µs under specified test conditions - parameters directly relevant to PWM-driven inductive loads.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 60 V - Maximum allowable collector-emitter voltage before breakdown; defines maximum supply rail compatibility in switch-mode circuits. |
| IC (DC) | 5 A - Continuous collector current rating at TA = 25 °C; determines steady-state load handling without forced cooling. |
| VCE(sat) | 0.1–0.3 V @ IC = 2 A, IB = 0.2 A - Low saturation voltage minimizes conduction loss and self-heating in high-current switching. |
| hFE (G grade) | 200–400 @ VCE = 1 V, IC = 2 A - High DC current gain reduces required base drive current and simplifies driver stage design. |
| PC (TA) | 1.3 W - Power dissipation limit at ambient temperature; requires thermal management above 25 °C per derating curve. |
| tstg | 1.1–2.5 µs - Storage time impacts switching speed in saturated-mode operation; critical for minimizing cross-conduction in H-bridge designs. |
Pinout & Package
Package: TO-126-3LD (Case 340AS), surface-mount compatible through-hole package with integral heat sink tab (Collector-connected). Mounting via screw or clamp recommended for thermal performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Emitting terminal for majority carriers | Connected to ground or low-side return path; polarity defines NPN topology and bias direction. |
| 2 (Collector) | Current-collecting terminal | Internally bonded to metal tab; must be electrically isolated from heatsink unless circuit design permits common connection. |
| 3 (Base) | Control electrode for carrier injection | Requires current-limited drive (max IB = 1 A DC); base resistor selection depends on hFE bin and desired saturation margin. |
Key Features
| Feature | Design Value |
|---|---|
| Low VCE(sat) | 0.1–0.3 V enables <1.5 W conduction loss at 5 A, reducing thermal stress in compact enclosures. |
| High hFE grade G | 200–400 gain range ensures reliable saturation with modest base drive, lowering gate-driver complexity in discrete BJT stages. |
| Complementary pairing | Designed as NPN counterpart to KSB1151 PNP, supporting matched push-pull output stages with symmetrical drive requirements. |
| Pulsed current capability | 8 A peak (PW ≤ 10 ms, duty ≤ 50%) extends usable current range beyond DC rating for intermittent loads like solenoids or motor startup. |
Applications
| DC Motor Control | Relay Driving |
|---|---|
Use Scenario: Controlling 12–24 V brushed DC motors in industrial actuators and automotive auxiliary systems. IC Role / Device Role / Timing Role: Main switching element in single-ended or H-bridge half-bridge configurations, handling bidirectional current flow when paired. Use Value: Low VCE(sat) reduces I²R losses during continuous conduction, while high hFE allows direct microcontroller GPIO drive with minimal external components. | Use Scenario: Energizing electromagnetic relays with coil currents up to 5 A in PLC I/O modules and power distribution panels. IC Role / Device Role / Timing Role: High-current switch replacing mechanical contacts; driven by logic-level signals with flyback diode protection. Use Value: Fast storage time (1.1–2.5 µs) and robust SOA ensure reliable turn-off under inductive kickback without snubber networks. |
| Linear Regulator Pass Element | Power Supply Output Stage |
Use Scenario: Series pass transistor in adjustable linear regulators delivering up to 3 A output current. IC Role / Device Role / Timing Role: Voltage-controlled current source operating in active region; dissipates excess input-output differential voltage. Use Value: 1.3 W ambient-rated dissipation and 150 °C junction temperature allow stable operation with moderate heatsinking at full load. | Use Scenario: Final output stage in unregulated or semi-regulated AC/DC supplies feeding downstream buck converters. IC Role / Device Role / Timing Role: Primary switching transistor in quasi-resonant or hard-switched topologies, often paralleled for higher current. Use Value: Pulse-rated 8 A capability supports short-term overload tolerance during cold-start or fault recovery without immediate failure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD127G | TO-252 (DPAK) package; lower PC = 1.25 W; VCEO = 60 V, IC = 4 A, hFE = 100–300 | Suitable for surface-mount PCBs with limited board space; not pin-compatible due to different footprint and thermal pad layout. | Select when SMT assembly is mandatory and thermal budget allows 0.05 W lower dissipation. |
| KSD1691YSTU | Same TO-126-3LD package and electrical specs; hFE grade Y (160–320) instead of G (200–400); Pb-free compliant | Identical mechanical fit and mounting; lower hFE requires ~20% higher base drive current for same collector current. | Choose when tighter hFE tolerance is acceptable and cost optimization is prioritized over maximum gain margin. |
Compared with MJD127G and KSD1691YSTU, the KSD1691GSTU offers the highest hFE bin and identical legacy TO-126 mechanical interface, making it preferable for through-hole designs requiring minimal base drive and proven thermal reliability - though all three share the same 60 V/5 A voltage-current envelope.
Availability
KSD1691GSTU is available at Aetrix Electronics and suitable for DC motor control, relay driving, and linear regulator pass element applications requiring stable component supply despite its discontinued status.
Supply support for KSD1691GSTU includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient power and signal management solutions for automotive, industrial, cloud, and consumer markets.
The KSD1691GSTU belongs to onsemi's legacy discrete power transistor family, engineered for robustness and predictable gain in high-current linear and switching applications where thermal stability and saturation performance are critical.
FAQ
Is KSD1691GSTU still in active production?
No, KSD1691GSTU has been officially marked as discontinued by onsemi per the January 2026 datasheet revision. However, Aetrix Electronics maintains legacy inventory and supports ongoing production runs with traceable, date-coded stock. The device remains fully functional and compliant with its original specifications, including Pb-free construction and TO-126-3LD mechanical form factor. Customers should plan for long-term obsolescence mitigation while leveraging existing supply.
What does the 'G' suffix in KSD1691GSTU indicate?
The 'G' in KSD1691GSTU denotes the hFE gain grade, specifying a DC current gain range of 200–400 measured at VCE = 1 V and IC = 2 A. This grading ensures consistent base drive requirements across units and supports reliable saturation in high-current switching applications. The 'TU' suffix indicates tape-and-reel packaging (1920 units/tube), while 'S' confirms Pb-free compliance per onsemi's environmental standards.
Can KSD1691GSTU replace KSD1691YS in an existing design?
Yes, KSD1691GSTU can replace KSD1691YS mechanically and electrically, as both use TO-126-3LD packaging and share identical absolute maximum ratings and electrical characteristics. The only difference is hFE grading: KSD1691YSTU is grade Y (160–320), while KSD1691GSTU is grade G (200–400). This means the KSD1691GSTU may achieve deeper saturation with the same base current, improving efficiency in marginal drive conditions - but no layout or schematic changes are needed.
What thermal considerations apply to KSD1691GSTU in continuous operation?
KSD1691GSTU has a 1.3 W power dissipation limit at TA = 25 °C, derating linearly to zero at 150 °C case temperature. For continuous 5 A operation, a heatsink maintaining TC ≤ 75 °C is strongly advised. The metal tab is electrically connected to the Collector, so isolation hardware (mica washer, silicone pad) must be used if mounting to a grounded heatsink. Thermal resistance from junction-to-case is not published, but typical TO-126 devices range from 2–4 °C/W.
How does KSD1691GSTU compare to its complementary PNP counterpart KSB1151?
KSD1691GSTU and KSB1151 are explicitly designed as complementary pairs: same voltage/current ratings (60 V, 5 A), matching SOA curves, and symmetric hFE profiles. The KSD1691GSTU's G-grade hFE (200–400) aligns with KSB1151's typical gain spread, enabling balanced drive in push-pull or Class AB amplifier outputs. Both share TO-126-3LD packaging, simplifying thermal and mechanical layout in dual-transistor configurations.
KSD1691GSTU Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-225AA, TO-126-3
- Packaging:
- Tube
- Product Status:
- Active
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 5 A
- Voltage - Collector Emitter Breakdown (Max):
- 60 V
- Vce Saturation (Max) @ Ib, Ic:
- 300mV @ 200mA, 2A
- Current - Collector Cutoff (Max):
- 10µA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 200 @ 2A, 1V
- Power - Max:
- 1.3 W
- Frequency - Transition:
- -
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-126-3
KSD1691GSTU FAQ
1.How can I place an order for KSD1691GSTU through Aetrix?
Please submit a Request for Quotation (RFQ) for KSD1691GSTU on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for KSD1691GSTU reliable?
The price and inventory of KSD1691GSTU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSD1691GSTU is usually 5 days.
3.What payment methods are accepted for KSD1691GSTU?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSD1691GSTU transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KSD1691GSTU?
KSD1691GSTU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KSD1691GSTU order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for KSD1691GSTU?
For technical support, including KSD1691GSTU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSD1691GSTU requirements.
6.How does Aetrix verify that KSD1691GSTU is sourced from the original manufacturer or authorized distributors?
All KSD1691GSTU products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that KSD1691GSTU meets industry standards.
7.What is the process for return or replacement of KSD1691GSTU?
All KSD1691GSTU units undergo pre-shipment inspection (PSI). If there is an issue with KSD1691GSTU, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The KSD1691GSTU part is unused and in its original packaging.
Return procedure for KSD1691GSTU:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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