Part A
FMMT717TA
Включенные диоды
- Lifecycle
- Active
- Stock
- 27774 ПКС
- Package
- TO-236-3
- Series
- Транзисторы - Биполярные (BJT) - Одиночные
Replacement verdict
Compatible functional replacement candidate
The FMMT717TA and FMMT720TC are both PNP silicon planar transistors in SOT-23 packages with comparable voltage and current ratings, making the FMMT720TC a viable functional replacement candidate for the FMMT717TA in most low-power switching and amplification applications. However, designers should validate DC current gain, saturation voltage, and transition frequency against the specific circuit requirements before committing to a drop-in substitution.
Transistor Polarity
High match
Package Type
High match
Collector Current Rating
Validation required
DC Current Gain
Validation required
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | FMMT717TA | FMMT720TC | Why it matters |
|---|---|---|---|
| Transistor Type | PNP | PNP | Both are PNP bipolar junction transistors, so polarity orientation in the circuit is the same. |
| Collector-Emitter Voltage (VCEO) | -12 V | -40 V | Higher VCEO allows the device to withstand larger collector-emitter voltages, affecting suitability for higher-voltage rails. |
| Collector Current (IC) | -2.5 A | -1.5 A | Maximum continuous collector current determines the load the transistor can drive without exceeding ratings. |
| DC Current Gain (hFE) | 300 (min) at IC = -1 A, VCE = -2 V | 100 (min) at IC = -1 A, VCE = -2 V | Higher gain reduces base drive requirements, which can simplify driver circuitry and lower input current. |
| Collector-Emitter Saturation Voltage (VCE(sat)) | -0.22 V max at IC = -1 A, IB = -10 mA | -0.33 V max at IC = -1 A, IB = -100 mA | Lower saturation voltage reduces conduction losses and heat dissipation in switching applications. |
| Transition Frequency (fT) | 120 MHz | 150 MHz | Higher fT supports faster switching and better performance in high-frequency amplification or switching circuits. |
| Power Dissipation (PD) | 625 mW | 500 mW | Power rating limits how much heat the package can safely dissipate, affecting continuous current capability. |
| Package / Mounting | SOT-23, Surface Mount | SOT-23, Surface Mount | Identical package and mounting style allow direct PCB footprint compatibility and drop-in replacement. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | FMMT717TA | FMMT720TC |
|---|---|---|
| Supplier | Diodes Incorporated | Diodes Incorporated |
| Part Status | Active | Obsolete |
| Transistor Type | PNP | PNP |
| Current - Collector(Ic)(Max) | 2.5 A | 1.5 A |
| Voltage - Collector Emitter Breakdown(Max) | 12 V | 40 V |
| Vce Saturation(Max) @ Ib Ic | 220mV @ 50mA, 2.5A | 330mV @ 100mA, 1.5A |
| Current - Collector Cutoff(Max) | 100nA | 100nA |
| DC Current Gain(h FE)(Min) @ Ic Vce | 300 @ 100mA, 2V | 300 @ 100mA, 2V |
| Power - Max | 625 mW | 625 mW |
| Frequency - Transition | 110MHz | 190MHz |
| Operating Temperature | -55°C ~ 150°C (TJ) | -55°C ~ 150°C (TJ) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the main differences between the FMMT717TA and FMMT720TC?
The FMMT717TA is a PNP silicon planar medium power transistor in a SOT-23 package, while the FMMT720TC is a PNP silicon planar medium power transistor also in a SOT-23 package. The primary differences lie in their voltage and current ratings, gain characteristics, and transition frequency, which make them suitable for different circuit applications.
What are the voltage and current ratings for the FMMT717TA?
The FMMT717TA has a collector-emitter voltage (VCEO) of -12 V, a collector-base voltage (VCBO) of -15 V, and a continuous collector current (IC) rating of -2.5 A. These ratings are specified in the manufacturer's datasheet.
What are the voltage and current ratings for the FMMT720TC?
The FMMT720TC has a collector-emitter voltage (VCEO) of -40 V, a collector-base voltage (VCBO) of -40 V, and a continuous collector current (IC) rating of -1.5 A. These ratings are specified in the manufacturer's datasheet.
Can the FMMT717TA and FMMT720TC be used interchangeably?
No, they are not direct substitutes. The FMMT717TA is rated for lower voltage (-12 V VCEO) but higher current (-2.5 A IC), while the FMMT720TC is rated for higher voltage (-40 V VCEO) but lower current (-1.5 A IC). Circuit designs must be validated against the specific voltage, current, and gain requirements.
What are the typical applications for the FMMT717TA?
The FMMT717TA is typically used in low-voltage, high-current switching applications such as DC-DC converters, motor drivers, and power management circuits where a -12 V VCEO and -2.5 A IC are sufficient.
What are the typical applications for the FMMT720TC?
The FMMT720TC is typically used in higher-voltage switching and amplification applications such as telecommunication line interfaces, high-voltage drivers, and general-purpose switching where a -40 V VCEO and -1.5 A IC are required.
What are the DC current gain (hFE) specifications for these transistors?
The FMMT717TA has a minimum hFE of 100 and a maximum of 300 at IC = -1 A, VCE = -2 V. The FMMT720TC has a minimum hFE of 100 and a maximum of 300 at IC = -0.5 A, VCE = -2 V. These values are typical and should be verified against the latest datasheet.
What is the transition frequency (fT) for the FMMT717TA and FMMT720TC?
The FMMT717TA has a typical transition frequency (fT) of 100 MHz. The FMMT720TC has a typical transition frequency (fT) of 150 MHz. These parameters indicate the high-frequency performance of each device.
What package type do the FMMT717TA and FMMT720TC use?
Both the FMMT717TA and FMMT720TC are supplied in the SOT-23 (TO-236AB) surface-mount package, which is a standard small-outline transistor package with three pins.