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onsemi KSD1691GS
- Part No.:
- KSD1691GS
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-225AA, TO-126-3
- Datasheet:
-
KSD1691GS.pdf
- Description:
- TRANS NPN 60V 5A TO-126-3
- Quantity:
- Payment:
- Shipping:
Inventory:1,789
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Product details
Overview
KSD1691GS 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; used in linear regulators and DC motor drive stages where low VCE(sat) (0.1–0.3 V at IC = 2 A) and high hFE (100–400 at IC = 2 A) are critical.
For engineers reviewing the KSD1691GS datasheet, pinout, applications, or equivalent options, key selection criteria include verified VCE(sat) performance under 2 A load, hFE grade G classification (200–400), TO-126 thermal derating behavior, and complementary pairing with KSB1151 for push-pull output stages.
Technical Context
This device operates as a medium-power NPN switching and linear amplifier transistor with fixed three-terminal topology. Its design emphasizes low saturation voltage and high DC current gain across 0.1–5 A operating range, supported by pulse-rated ICP = 8 A (PW ≤ 10 ms, duty ≤ 50%) and safe operating area defined up to 100 V and 10 A in pulsed conditions.
Thermal management relies on case-mounted heat sinking: PC = 20 W at TC = 25 °C, derated linearly above 25 °C per Figure 7, with maximum junction temperature of 150 °C and storage range from −55 °C to 150 °C. The TO-126-3LD package provides direct metal tab thermal path and standardized lead spacing for through-hole PCB mounting.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 60 V - Maximum continuous collector-emitter voltage before breakdown; defines upper rail limit in switch-mode or linear regulator designs. |
| IC (DC) | 5 A - Sustained collector current capability; sets baseline for continuous load handling without forced cooling. |
| VCE(sat) | 0.1–0.3 V @ IC = 2 A, IB = 0.2 A - Low conduction loss enabling >98% efficiency in 12 V/2 A switching applications. |
| hFE | 100–400 @ IC = 2 A - High DC gain reduces required base drive current, easing driver stage design. |
| PC (TA) | 1.3 W @ TA = 25 °C - Ambient-limited power dissipation; requires heatsinking for >1 W continuous operation. |
| TJ(max) | 150 °C - Absolute maximum junction temperature; constrains thermal design margin in sealed enclosures. |
Pinout & Package
Package: TO-126-3LD (Case 340AS), thermally enhanced through-hole package with insulated collector tab, 3.4 mm lead pitch, and 15.2 mm × 10.2 mm footprint. Mounting requires mechanical fastening of collector tab to heatsink.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current sink terminal | Low-impedance return path; connected to ground or negative rail in common-emitter configurations. |
| 2 (Collector) | Current source terminal | Electrically isolated metal tab; must be mounted to heatsink with thermal interface material for PC > 1 W. |
| 3 (Base) | Control input terminal | High-impedance gate for current amplification; requires 0.2 A drive for full saturation at 2 A load. |
Key Features
| Feature | Design Value |
|---|---|
| Low VCE(sat) | 0.1–0.3 V enables <0.6 W conduction loss at 2 A, reducing thermal stress in compact power stages. |
| Complementary pairing | Explicitly matched to KSB1151 PNP for Class B/AB audio and motor H-bridge output stages. |
| hFE grade G | Guaranteed 200–400 gain at IC = 2 A ensures consistent base drive sizing across production lots. |
| Pulse current rating | 8 A peak (10 ms, 50% duty) supports short-term surge loads like motor startup or inrush limiting. |
Applications
| Linear Voltage Regulator | DC Motor Driver |
|---|---|
Use Scenario: Adjustable 3–15 V, 2 A linear regulator using LM317 pass element configuration. IC Role / Device Role / Timing Role: Pass transistor controlling output voltage via emitter-follower feedback loop. Use Value: VCE(sat) ≤ 0.3 V minimizes dropout voltage and heat generation at full 2 A load. | Use Scenario: Unidirectional 12 V DC brushed motor control with PWM input and freewheeling diode. IC Role / Device Role / Timing Role: High-side switch in open-collector driver stage. Use Value: 5 A DC rating and 8 A pulse support handle 3× stall current during acceleration. |
| Audio Power Amplifier | Power Supply OR-ing |
Use Scenario: Complementary Class AB output stage with KSB1151 in 10 W mono amplifier. IC Role / Device Role / Timing Role: NPN half of push-pull emitter-follower pair driving 4 Ω speaker load. Use Value: Matched hFE and VCE(sat) with KSB1151 reduces crossover distortion and thermal imbalance. | Use Scenario: Redundant 5 V/3 A power supply OR-ing using discrete diode-replacement topology. IC Role / Device Role / Timing Role: Active switch replacing Schottky diode to reduce forward drop and improve efficiency. Use Value: 0.1 V typical VCE(sat) cuts conduction loss by 85% vs. 0.45 V Schottky, lowering thermal load in parallel PSUs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MJD122G | VCEO = 100 V, IC = 8 A, PC = 1.5 W, TO-252 package; higher voltage rating but surface-mount only. | Requires PCB redesign for SMT layout; unsuitable for through-hole legacy systems. | Select when >60 V rail voltage or automated assembly is required. |
| 2SC5200 | VCEO = 230 V, IC = 15 A, PC = 150 W, TO-3P package; significantly higher power and voltage capability. | Over-specified for 60 V/5 A use cases; demands larger heatsink and mechanical mounting. | Select only when scaling to >10 A continuous or >100 V operation. |
Compared with MJD122G and 2SC5200, the KSD1691GS offers optimal balance of through-hole mountability, 60 V/5 A rating, and low VCE(sat) in cost-sensitive industrial controls-avoiding SMT retooling or over-engineered thermal solutions.
Availability
KSD1691GS is available at Aetrix Electronics and suitable for linear regulators, DC motor drivers, audio amplifier output stages, and power supply OR-ing circuits requiring stable component supply despite onsemi's discontinuation notice.
Supply support for KSD1691GS 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 electronics, delivering power, analog, sensor, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
The KSD1691GS belongs to onsemi's legacy bipolar power transistor family designed specifically for cost-optimized, medium-current linear and switching applications in industrial power supplies and motor controls.
FAQ
Is KSD1691GS still in active production?
No, KSD1691GS is marked as discontinued by onsemi per Revision 1 (January 2026) of its datasheet. However, Aetrix Electronics maintains inventory and offers lifecycle support including last-time buys, cross-reference assistance, and controlled distribution for legacy system maintenance. The KSD1691GS remains fully functional and electrically identical to its active predecessor versions.
What does the 'G' suffix in KSD1691GS indicate?
The 'G' in KSD1691GS denotes the hFE gain grade per onsemi's classification table: hFE2 (measured at VCE = 1 V, IC = 2 A) falls within 200–400. This grade ensures predictable base drive requirements and consistent current amplification across units, critical for production-line calibration of driver circuits using the KSD1691GS.
Can KSD1691GS replace KSD1691YSTU in existing designs?
Yes, KSD1691GS and KSD1691YSTU share identical electrical specifications, TO-126-3LD package, and marking format-differing only in hFE grade (Y = 160–320 vs. G = 200–400) and packaging quantity (2000 BLKBG vs. 1920 Units/Tube). The KSD1691GS is a direct functional replacement where higher minimum hFE is acceptable or beneficial.
What thermal interface material is recommended for KSD1691GS mounting?
For reliable thermal transfer, use silicone-based thermal grease (e.g., Dow Corning TC-5123) or 0.1 mm thick thermally conductive silicone pad (e.g., Laird Tflex 400) between the KSD1691GS collector tab and aluminum heatsink. Avoid electrically conductive pastes unless isolation is confirmed, as the TO-126 collector tab is internally connected to pin 2 and must remain at system potential.
Does KSD1691GS support pulse-width modulation (PWM) switching?
Yes, KSD1691GS supports PWM operation with validated timing: tON = 0.2–1 µs, tSTG = 1.1–2.5 µs, and tF = 0.2–1 µs under VCC = 10 V, IC = 2 A conditions. Its low storage time enables clean turn-off at ≤100 kHz PWM frequencies, making it suitable for DC motor speed control and SMPS pre-regulator stages using the KSD1691GS.
KSD1691GS Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-225AA, TO-126-3
- Packaging:
- Bulk
- 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
KSD1691GS FAQ
1.How can I place an order for KSD1691GS through Aetrix?
Please submit a Request for Quotation (RFQ) for KSD1691GS 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 KSD1691GS reliable?
The price and inventory of KSD1691GS are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSD1691GS is usually 5 days.
3.What payment methods are accepted for KSD1691GS?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSD1691GS transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KSD1691GS?
KSD1691GS orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KSD1691GS 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 KSD1691GS?
For technical support, including KSD1691GS datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSD1691GS requirements.
6.How does Aetrix verify that KSD1691GS is sourced from the original manufacturer or authorized distributors?
All KSD1691GS 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 KSD1691GS meets industry standards.
7.What is the process for return or replacement of KSD1691GS?
All KSD1691GS units undergo pre-shipment inspection (PSI). If there is an issue with KSD1691GS, 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 KSD1691GS part is unused and in its original packaging.
Return procedure for KSD1691GS:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
KSD1691GS Tags
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MMBT3906LT1G
onsemi
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MMBT3904-7-F
Diodes Incorporated
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MMBT3904LT1G
onsemi
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MMBT3906-7-F
Diodes Incorporated
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MMBT3904-TP
Micro Commercial Co
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MMBT2222A-7-F
Diodes Incorporated
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BC846BLT1G
onsemi
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BC847B,215
Nexperia USA Inc.
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SMMBT3904LT1G
onsemi
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MMBT2222A-TP
Micro Commercial Co
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MMBTA06LT1G
onsemi
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onsemi
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