STMicroelectronics STA505

Overview

STA505 from STMicroelectronics is a monolithic quad half-bridge power stage in MultiPower BCD technology, configured as dual BTL (50+50W @ 30V/8Ω, THD=10%) or single BTL (80W @ 36V/8Ω). It features 200 mΩ R_ds(on) complementary DMOS outputs, CMOS-compatible logic inputs, thermal warning (TH_WAR) and fault (FAULT) open-collector outputs, and under-voltage protection at 7 V.

For engineers reviewing the STA505 datasheet, STA505 pinout, STA505 application, or STA505 equivalent, key selection criteria include its 3.5 A continuous output current per half-bridge, 384 kHz switching frequency support, configurable CONFIG pin for dual/single/half-bridge modes, and integrated thermal shutdown at 150 °C with 25 °C hysteresis.

Technical Context

The STA505 implements four independent half-bridge stages with matched P/N-channel DMOS outputs (95% R_ds(on) matching), driven by logic-level inputs referenced to VL (adjustable threshold). Its dead-time control includes static (10–20 ns) and dynamic (50 ns) modes to prevent shoot-through during high-current switching.

Protection architecture integrates undervoltage lockout (7 V), thermal warning at 130 °C, full thermal shutdown at 150 °C, and short-circuit current limiting (3.5–8 A). The CONFIG pin reconfigures topology: grounded for dual bridge, tied to Vdd for single BTL (doubled current), or floating for binary half-bridge mode.

Key Specifications

Pinout & Package

STA505 uses PowerSO36 package (slug-up thermal pad), measuring 15.8 × 13.9 mm with 36 leads and 2.5 °C/W junction-to-case thermal resistance. The exposed thermal pad must be soldered to PCB copper for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad half-bridge power stage applications.

Compared with TAS5630 and IRS2092S, STA505 uniquely combines topology reconfigurability (CONFIG pin), integrated thermal warning signaling, and matched DMOS outputs in a single PowerSO36 package-making it optimal for space-constrained, thermally managed DDX™ audio systems where flexibility and built-in diagnostics are prioritized over ultra-low R_ds(on) or extreme voltage range.

Availability

STA505 is available at Aetrix Electronics and suitable for home theater audio amplifiers, automotive infotainment systems, and professional audio DSP amplifiers requiring stable component supply and long-lifecycle support.

Supply support for STA505 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, Switzerland, specializing in power management, analog, MEMS, and microcontroller technologies for industrial, automotive, and consumer markets.

The STA505 belongs to ST's DDX™-optimized audio power stage product line, designed specifically to serve as the output stage for high-efficiency all-digital Class-D amplifiers targeting THD <10% at full rated power into 4–8 Ω loads.

FAQ

What is the function of the CONFIG pin on STA505?

The CONFIG pin determines bridge topology: grounded for dual-bridge mode (two independent full bridges), tied to Vdd for single-BTL mode (doubled current capability), or left floating for binary half-bridge mode (half current per channel). This pin enables hardware-level reconfiguration without changing external circuitry or firmware.

Does STA505 require external bootstrap capacitors?

No. STA505 integrates internal charge pumps and bootstrap circuitry for high-side gate drive, eliminating the need for external bootstrap capacitors. This simplifies PCB layout and improves reliability in high-density audio amplifier designs where space and component count are critical constraints.

How does the thermal warning (TH_WAR) output behave?

TH_WAR is an open-collector output that pulls low at 130 °C junction temperature, indicating thermal stress before shutdown. It remains low until junction temperature drops below 105 °C (130 °C – 25 °C hysteresis). External pull-up resistor is required; no internal pull-up is provided.

Can STA505 operate with a 5 V logic supply?

Yes. The VL pin sets input threshold voltage (V_IN-H = VL/2 + 300 mV, V_IN-L = VL/2 − 300 mV). With VL = 5 V, thresholds become 2.8 V and 2.2 V - compatible with standard 5 V CMOS logic. The Vdd regulator internally generates 5 V referenced to GND-Reg for internal logic.