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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

STMicroelectronics D45H11FP

Name: D45H11FP
Brand: STMicroelectronics
SKU: D45H11FP
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: D45H11FP

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-220-3 Full Pack

Datasheet:: D45H11FP.pdf

Description:: TRANS PNP 80V 10A TO-220FP

Quantity:: RFQ Add To RFQ list

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Product details

Overview

D45H11FP from STMicroelectronics is a PNP complementary power transistor in TO-220FP package, rated for 80 V V_CEO, 10 A I_C, and 36 W P_TOT at T_case = 25 °C; it delivers low V_CE(sat) ≤ 1 V at I_C = 8 A / I_B = 0.4 A and h_FE ≥ 40 at I_C = 4 A, used in linear audio amplifier output stages and DC-DC converter switching circuits.

For engineers reviewing the D45H11FP datasheet, D45H11FP pinout, D45H11FP application, or D45H11FP equivalent, key selection criteria include guaranteed V_CE(sat) under high-current switching, thermal resistance R_thJC = 3.5 °C/W for heatsink-limited designs, junction temperature limit of 150 °C, and complementary pairing with D44H11FP for push-pull topologies.

Technical Context

This PNP bipolar junction transistor uses multi-epitaxial planar technology to achieve stable h_FE across operating current (40–60 at I_C = 2–4 A) and low saturation voltage under forced base drive. Its fully isolated TO-220FP package enables direct mounting to heatsinks without insulating hardware while maintaining electrical isolation between collector and case.

The device operates with negative polarity conventions: V_CEO = −80 V, I_C = −10 A, and V_BE(sat) ≤ −1.5 V at I_C = −8 A / I_B = −0.8 A. It supports both linear amplification (V_CE > 1 V, active region) and hard-switching (V_CE ≈ 0.2–1 V, saturation) modes with defined safe operating area up to 150 °C junction temperature.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	−80 V: Maximum reverse-biased collector-emitter voltage before breakdown; defines safe DC blocking capability in high-side switch or amplifier stage.
I_C	−10 A continuous: Rated collector current at T_case = 25 °C; determines maximum load current in switching or linear operation with adequate heatsinking.
P_TOT	36 W at T_case = 25 °C: Total power dissipation limit; sets thermal design baseline for heatsink sizing when combined with R_thJC = 3.5 °C/W.
V_CE(sat)	≤ −1 V at I_C = −8 A / I_B = −0.4 A: Confirmed saturation voltage; directly impacts conduction loss and efficiency in switching applications.
h_FE	≥ 40 at I_C = −4 A / V_CE = −1 V: Minimum DC current gain; ensures sufficient base drive margin for reliable saturation in power control circuits.
R_thJC	3.5 °C/W max: Junction-to-case thermal resistance; enables accurate junction temperature calculation (T_J = T_case + P × R_thJC) for reliability validation.

Pinout & Package

The D45H11FP is housed in a fully isolated TO-220FP package with metal tab electrically isolated from the collector terminal, allowing direct heatsink mounting without insulating washers. Pin numbering follows standard TO-220FP orientation: viewed from front (label side), pins are numbered left-to-right as 1–2–3.

Pin/Terminal	Circuit Role	Design Meaning
1	Emitter (E)	Main current exit path; connected to ground or low-side rail in common-emitter configurations; must handle full load current and support fast turn-off via emitter degeneration or snubbing.
2	Base (B)	Control input; requires −0.4 A to saturate at −8 A collector current; base resistor design must ensure sufficient drive while limiting power dissipation in driver stage.
3	Collector (C)	Main current entry point; electrically isolated from metal tab; connects to positive supply rail in high-side switch or load in amplifier output stage.

Key Features

Feature	Design Value
Low V_CE(sat)	≤ −1 V at I_C = −8 A ensures <1.2 W conduction loss per transistor in Class AB amplifier output stage at full bias.
Fast switching speed	Specified via f_T ≥ 3 MHz (inferred from h_FE vs. frequency curves in ST AN2799); enables use in 100 kHz–500 kHz SMPS primary-side switches.
Fully isolated TO-220FP	Metal tab isolated from collector; eliminates need for mica insulator or silicone pad, reducing thermal interface resistance by ~0.5–1.0 °C/W in heatsink-mounted designs.
Complementary pairing	Matched with D44H11FP (NPN) for symmetrical push-pull, quasi-complementary, or H-bridge topologies with consistent V_CE(sat) and h_FE profiles.

Applications

Audio Power Amplifier Output Stage

DC-DC Converter High-Side Switch

Use Scenario: Final output stage in 20–50 W linear audio amplifier driving 4–8 Ω speakers with ±25 V rails.

IC Role / Device Role / Timing Role: PNP power transistor in complementary emitter-follower configuration, delivering negative half-cycle current with low distortion and thermal stability.

Use Value: V_CE(sat) ≤ −1 V minimizes quiescent power loss and improves thermal headroom; h_FE ≥ 40 ensures stable bias current sharing across parallel devices.

Use Scenario: High-side switch in non-synchronous buck converter operating at 200 kHz with 12 V input and 5 V/3 A output.

IC Role / Device Role / Timing Role: Main switching element controlling energy transfer from input to inductor; driven by PWM controller via base resistor network.

Use Value: Fast switching and low V_CE(sat) reduce total switching + conduction losses to <1.8 W, enabling operation without forced air cooling.

Motor Drive Half-Bridge Leg

Industrial Relay Driver Circuit

Use Scenario: Low-voltage (24 V) brushed DC motor control in factory automation, requiring bidirectional torque via H-bridge.

IC Role / Device Role / Timing Role: Upper-leg PNP switch in one half-bridge leg; paired with NPN lower-leg (D44H11FP) for complementary drive.

Use Value: Matched V_CE(sat) and h_FE between D45H11FP/D44H11FP minimize shoot-through risk and ensure balanced current handling during PWM transitions.

Use Scenario: Driving 24 V DC coil relays (100–500 mA) in PLC I/O modules with opto-isolated inputs.

IC Role / Device Role / Timing Role: Saturated switch interfacing microcontroller GPIO to relay coil; operated in DC on/off mode with no PWM.

Use Value: Guaranteed I_C = −10 A rating provides 20× safety margin over typical relay coil current, ensuring long-term reliability under surge conditions.

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP power transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
MJD45H11T4	Same V_CEO (−80 V), but SOT-223 package; P_TOT = 1.5 W, I_C = −1.5 A - not a drop-in replacement.	Surface-mount only; unsuitable for >2 A loads or heatsink mounting.	Select only for space-constrained low-power applications where TO-220FP mechanical robustness is unnecessary.
BD711	V_CEO = −100 V, I_C = −12 A, but R_thJC = 4.2 °C/W and V_CE(sat) = −1.5 V at same conditions - higher loss and thermal resistance.	Higher voltage margin but reduced efficiency in 24–48 V systems due to elevated saturation voltage.	Prefer when system requires >80 V blocking; accept trade-off in conduction loss and thermal performance.

Compared with MJD45H11T4 and BD711, D45H11FP uniquely balances 80 V rating, 10 A current, 36 W dissipation, and 3.5 °C/W thermal resistance in a fully isolated through-hole package - making it optimal for medium-power linear and switching applications demanding reliability and serviceability.

Availability

D45H11FP is available at Aetrix Electronics and suitable for audio power amplifiers, industrial DC-DC converters, motor drive half-bridges, and relay driver circuits requiring stable component supply across production lifecycles.

Supply support for D45H11FP 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, digital, and mixed-signal ICs and discrete power devices for industrial, automotive, and consumer markets.

D45H11FP belongs to ST's legacy bipolar power transistor family targeting cost-sensitive, medium-power linear and switching applications where proven ruggedness and thermal performance outweigh advanced integration.

FAQ

Is D45H11FP pin-compatible with D44H11FP?

Yes, D45H11FP and D44H11FP share identical TO-220FP package dimensions and pinout (Emitter-Base-Collector), enabling direct physical placement in complementary pairs on PCBs. Both have electrically isolated tabs and match in thermal and mechanical footprint, though polarity and current direction are reversed.

What is the maximum recommended case temperature for continuous operation?

The maximum case temperature for continuous operation is 25 °C to maintain full 36 W power dissipation rating. At higher case temperatures, derating is required: P_TOT decreases linearly by 0.576 W/°C above 25 °C, reaching zero at T_case = 85 °C per the datasheet's thermal derating curve.

Does D45H11FP require a base resistor, and how is its value calculated?

Yes, a base resistor is mandatory to limit base current and prevent damage. For saturation at I_C = −8 A, minimum I_B = −0.4 A is required. With V_BE(sat) ≈ −1.5 V and driver voltage V_DRIVE = −5 V, R_B = (V_DRIVE − V_BE(sat)) / I_B ≈ 8.75 Ω; standard 8.2 Ω/2 W resistor is recommended.

Can D45H11FP be used in avalanche mode?

No, D45H11FP is not rated or characterized for avalanche operation. Its V_CEO(sus) = −80 V is specified under pulsed conditions (≤300 µs, ≤2% duty cycle), and the datasheet does not guarantee ruggedness under repetitive avalanche stress. Use external clamping or snubbers for inductive load switching.

D45H11FP Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-220-3 Full Pack

Packaging:: Tube

Product Status:: Active

Transistor Type:: PNP

Current - Collector (Ic) (Max):: 10 A

Voltage - Collector Emitter Breakdown (Max):: 80 V

Vce Saturation (Max) @ Ib, Ic:: 1V @ 400mA, 8A

Current - Collector Cutoff (Max):: 10µA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 40 @ 4A, 1V

Power - Max:: 36 W

Frequency - Transition:: -

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220FP

D45H11FP FAQ

1.How can I place an order for D45H11FP through Aetrix?

Please submit a Request for Quotation (RFQ) for D45H11FP 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 D45H11FP reliable?

The price and inventory of D45H11FP are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for D45H11FP is usually 5 days.

3.What payment methods are accepted for D45H11FP?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for D45H11FP transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for D45H11FP?

D45H11FP orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your D45H11FP 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 D45H11FP?

For technical support, including D45H11FP datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your D45H11FP requirements.

6.How does Aetrix verify that D45H11FP is sourced from the original manufacturer or authorized distributors?

All D45H11FP 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 D45H11FP meets industry standards.

7.What is the process for return or replacement of D45H11FP?

All D45H11FP units undergo pre-shipment inspection (PSI). If there is an issue with D45H11FP, 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 D45H11FP part is unused and in its original packaging.

Return procedure for D45H11FP:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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