onsemi 2SA1723

Overview

2SA1723 from SANYO is a PNP epitaxial planar silicon transistor designed for high-frequency amplifier and medium-power amplifier applications, featuring f_T = 1.5 GHz (typ), V_CEO = −30 V, I_C = −300 mA, P_C = 1.2 W (T_a = 25°C), and TO-126 package. It serves as an RF driver or wideband gain stage in VHF/UHF signal chains.

For engineers reviewing the 2SA1723 datasheet, pinout, applications, or equivalent options, key selection criteria include its high f_T, low V_CE(sat) at −300 mA, DC current gain h_FE ≥ 100 at I_C = −5 mA, reverse transfer capacitance C_re = 0.5 pF at V_CB = −10 V, and suitability for pulsed RF amplification up to 1 GHz.

Technical Context

The 2SA1723 uses SANYO's FBET (Flat Base Epitaxial Transistor) process to achieve high-speed switching and stable gain across VHF bands. Its PNP polarity, −30 V V_CEO, and −20 V V_CBO support operation in negative-rail RF amplifier stages with moderate voltage headroom.

Electrical behavior is characterized by h_FE = 100–300 at I_C = −5 mA and V_CE = −5 V, V_CE(sat) ≤ −0.4 V at I_C = −300 mA/I_B = −30 mA, and C_ob = 5.8 pF at V_CB = −10 V - enabling broadband matching with minimal neutralization.

Key Specifications

Pinout & Package

2SA1723 is housed in a JEDEC TO-126 molded plastic package with exposed collector tab for thermal conduction. Pin 1 = Emitter, Pin 2 = Collector (tab-connected), Pin 3 = Base - standard configuration for through-hole mounting and heatsink attachment.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP high-frequency amplifier applications.

Compared with 2SA1723, both alternatives trade off high-frequency gain for either higher breakdown voltage (MPSA92) or wider safe-operating-area voltage range (2SA1015), making them unsuitable as drop-in replacements in VHF/UHF amplifier designs requiring ≥1 GHz f_T and ≥300 mA output current.

Availability

2SA1723 is available at Aetrix Electronics and suitable for VHF wideband amplifiers, UHF RF driver stages, FM broadcast modulator circuits, and industrial RF heating control systems requiring stable component supply and long-term obsolescence management.

Supply support for 2SA1723 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

SANYO Electric Co., Ltd. was a Japanese semiconductor manufacturer known for high-performance analog and RF discrete devices before its acquisition by Panasonic in 2011.

The 2SA1723 belongs to SANYO's high-frequency PNP transistor family developed specifically for VHF/UHF amplifier and driver applications demanding high f_T, stable h_FE, and robust thermal performance in TO-126 packaging.

FAQ

What is the maximum collector current rating for the 2SA1723?

The 2SA1723 has an absolute maximum collector current rating of −300 mA under DC conditions. This value is confirmed in the Absolute Maximum Ratings table on page 1 of the official SANYO datasheet (No.4668–1/3). Continuous operation at this current requires adherence to derated power dissipation limits - for example, P_C drops to 0.6 W at T_a = 70°C. The 2SA1723 supports short-duration pulse currents up to −600 mA, as shown in the I_C–V_CE curves (ITR04379).

Does the 2SA1723 have a documented f_T specification, and what is its typical value?

Yes, the 2SA1723 has a documented gain-bandwidth product: f_T = 1.5 GHz (typical) at V_CE = −5 V, I_C = −100 mA, and f = 100 MHz, per the Electrical Characteristics table (No.4668–2/3). This parameter is measured and guaranteed across production lots using SANYO's FBET process. The 2SA1723 maintains usable gain up to approximately 900 MHz in practical amplifier designs, making it suitable for UHF driver applications where the 2SA1723 is deployed as a broadband gain block.

What package type does the 2SA1723 use, and how are its pins arranged?

The 2SA1723 uses a JEDEC-standard TO-126 plastic package with an exposed collector tab. Pin numbering is defined with the flat side facing the viewer: Pin 1 = Emitter, Pin 2 = Collector (electrically and thermally connected to the metal tab), Pin 3 = Base. This arrangement is explicitly illustrated in the Package Dimensions diagram (No.4668–2/3) and verified across SANYO's ordering documentation (ENN4668). The 2SA1723 requires mechanical isolation of the collector tab from chassis ground when mounted to a heatsink.

Can the 2SA1723 be used in linear amplifier applications, and what is its DC current gain range?

Yes, the 2SA1723 is specified for linear amplifier use, with h_FE ranging from 100 to 300 at V_CE = −5 V and I_C = −5 mA. This range is confirmed in the Electrical Characteristics table (No.4668–2/3) and supported by h_FE–I_C curves (ITR04380). The 2SA1723 maintains stable gain across its operating current range, enabling predictable biasing in Class-A and Class-AB configurations - a key reason the 2SA1723 is selected for FM modulator and wideband preamplifier designs.

What are the thermal limitations of the 2SA1723, and how does power dissipation change with temperature?

The 2SA1723 has a maximum junction temperature of 150°C and a storage temperature range of −55°C to +150°C. Its power dissipation derates linearly above T_a = 25°C: P_C = 1.2 W at 25°C, falling to zero at ~150°C ambient (per PC–Ta curve ITR04385). When mounted on a heatsink, P_C vs. case temperature (T_c) shows 1.2 W at T_c = 25°C, dropping to ~0.6 W at T_c = 100°C (ITR04386). These thermal characteristics directly impact reliability in continuous RF service - critical for ensuring long-term stability of the 2SA1723 in production amplifiers.