Silicon Labs: Launches Automotive-Grade High-Side Switch TPW4020DQ

Amid the sweeping trends of electrification and intelligentization, high-side switches serve as a critical interface between digital control systems and physical actuators, making their performance of paramount importance. To meet the stringent demands of the premium market for superior performance, reliability, and advanced intelligence, Silipu has officially launched the next-generation, high-end, dual-channel smart high-side switch TPW4020DQ, specifically designed for body electronics control applications.

 

I. China’s First High-Power Single-Die High-Side Switch Solution

The introduction of the TPW4020DQ marks several key breakthroughs for Silergy in the field of intelligent power devices. It is not a simple power switch; rather, it is an integrated smart power-management and safety-control unit that combines driving, sensing, and protection functions. The product’s core advantages stem from its innovative VDMOS + BCD integrated process platform and its more comprehensive protection features. In conventional domestic high-side chip solutions, the control chip and the power MOSFET are manufactured separately and interconnected via wire bonding on the package substrate. However, this approach suffers from additional parasitic parameters introduced by the wire bonds, which can degrade performance at high frequencies and under high-current conditions, resulting in lower reliability compared with single-chip integration solutions.

The TPW4020DQ is China’s first high-power, single-die, high-side switch, reducing the on-resistance of a single channel to an industry-leading 20 mΩ at room temperature (25°C), thereby significantly minimizing conduction losses and heat generation. At the same time, its chip layout and thermal management have been optimized, creating additional space for integrating high-precision monitoring circuits. In terms of the comprehensiveness and reliability of its protection features, the TPW4020DQ is on par with international manufacturers, offering such protections as overcurrent/short-circuit current limiting to support more demanding high-capacitance power-up scenarios; absolute overtemperature self-protection and thermal-gradient self-protection; intelligent power-lockout; self-protection against reverse connection of the power transistor to the supply or ground; self-protection against reverse connection of the power transistor to the supply or output; self-protection against loss of ground or supply; and overvoltage/undervoltage protection, among others.

TPW4020DQ Product Features:

• Supports 12V vehicle power supply applications

• Typical on-state resistance: 20 mΩ

• 5A continuous overcurrent capability per channel

• When outputting 2 A, the current-sensing accuracy reaches ±4%.

• Features Reverse On and Inverse On protection

• Loss of GND protection function

• Operating temperature: -40°C to 125°C

• Package: EQSOP14, enabling direct pin-to-pin replacement with mainstream industry solutions.

Figure 1: Internal Block Diagram of the TPW4020DQ System

1. Ultra-wide power supply operating range, compatible with all in-vehicle power sources

Figure 1 shows the internal block diagram of the TPW4020DQ system. The TPW4020DQ delivers industry-leading performance specifications:

It operates over a wide input voltage range of 4 to 28 V and integrates high-precision, real-time load-current monitoring (with an accuracy of ±4% at load currents above 2 A) as well as multiple voltage-clamping protection mechanisms.

The TPW4020DQ single-channel converter can sustain a load current of 10 A at ambient temperature (25°C) and delivers a transient output current capability of up to 50 A, easily handling surge currents that are several times higher than those in typical applications, such as motor-starting scenarios.

2. A unique protection mechanism enables power-up with large capacitive loads.

By effectively integrating an intelligent latch protection mechanism with a unique fault-retry scheme, the TPW4020DQ can not only completely shut down and latch off a channel when it detects persistent severe faults such as overcurrent or overtemperature, requiring an external reset to resume operation—thereby effectively preventing fault escalation—but also support power-up with large-capacitance loads, thus avoiding termination of the power-up sequence by the latch protection mechanism.

3. High-standard reliability testing to confidently handle extreme voltage surges in automotive applications.

In terms of test and validation, the TPW4020DQ has also passed ISO 7637-2 and ISO 16750-2 automotive-grade waveform tests, the AEC-Q100-012 repetitive short-circuit reliability test, and the Emax demagnetization limit test for inductive loads. Notably, the AEC-Q100-012 places extremely stringent requirements on the short-circuit reliability of high-side switches; even after undergoing cyclic short-circuit testing at output loads with 0 µH and 5 µH inductance—more than 1 million cycles—the TPW4020DQ continues to maintain normal device functionality. In addition, the TPW4020DQ incorporates Reverse-On and Inverse-On protection features: the former automatically turns on the power switch when the supply is reverse-connected, while the latter ensures that the power switch does not inadvertently turn off even when a reverse current flows back from the output during normal operation, thereby providing robust protection for the power switch.

Table 1: Comparison of Key Specifications for TPW4020DQ

 

II. Empowering Customer Design

In the mid- to high-end market, demand for high-side switches is complex and diverse; however, accurately identifying these needs, delivering products that precisely meet customer requirements, and gaining market acceptance remain among the most significant challenges faced by chip manufacturers during product development.

Sirep adopts a strategy of “benchmarking performance as the foundation and leveraging service and cost as the breakthrough,” delving deep into various industries to identify core pain points and develop high-side switch products that precisely meet customer needs. In terms of performance, Sirep has already achieved a domestically leading level in key metrics such as on-resistance, single-die design capability, and stability, with on-resistance as low as 20 mΩ. Moreover, the single-die design offers lower parasitic parameters and higher integration compared with multi-chip packaging solutions, making it suitable for a wide range of application scenarios—this forms the cornerstone of its competitive advantage.

TPW4020DQ is designed to meet engineers’ practical design needs and delivers comprehensive customer value across four key dimensions.

1. Cost Optimization and Efficiency Improvement

The ultra-low on-resistance of 20 mΩ directly reduces power consumption and thermal management costs, while the EQSOP-14 package ensures pin compatibility with mainstream international competitors, facilitating rapid replacement and upgrades for customers. The integrated internal ground network eliminates the need for external components, lowering BOM costs and PCB footprint, and further enables reverse-polarity tolerance—meaning that even in the unlikely event of incorrect wiring on-site, the chip will avoid immediate damage, providing critical fault-tolerant capability for the system.

2. Comprehensive load monitoring and reliable harness protection

Real-time, high-precision current monitoring coupled with comprehensive diagnostic and protection mechanisms. Take in-vehicle systems as an example: components such as the electric power-assisted steering motor, brake solenoid valves, seat adjustment motors, and LED lighting systems all rely on high-precision current feedback to achieve precise control. High-precision current monitoring enables real-time feedback of the load’s operating current to the domain-control MCU, which then adjusts the PWM duty cycle to precisely regulate motor torque, solenoid valve opening, LED brightness, and other parameters, thereby enabling more refined load control. At the same time, current data can be used to determine whether the load is functioning properly—for instance, whether a solenoid valve is engaging correctly or whether a motor is stalled—allowing for timely adjustments to the control strategy.

3. High System Robustness in Extreme Operating Environments

The in-vehicle environment is characterized by severe conditions, including strong electromagnetic interference, significant battery voltage fluctuations (such as sudden voltage drops during engine start-up and voltage spikes during load rejection), and wide temperature variations. VS-GND and VS-IS voltage clamping enable the chip to withstand abrupt voltage transients, thereby preventing system failures. Additionally, VDS voltage clamping combined with current-limiting mechanisms, along with absolute temperature and temperature-gradient protection, effectively safeguard the system against failures caused by inductive kickback or overcurrent in long-distance wiring during power interruptions or short circuits.

4. Support for full-lifecycle fault diagnosis and root-cause analysis

To meet the mandatory compliance requirements of ISO 26262 functional safety, based on internal fault diagnostics—including overcurrent detection and absolute/temperature-gradient monitoring—high-precision current monitoring effectively distinguishes between normal fluctuations and actual faults, thereby preventing both false triggers and missed triggers and enhancing system stability in complex environments.

 

III. Key Application Scenarios: Tackling High-End, Stringent Applications

Figure 2: Typical Application Block Diagram of TPW4020DQ

The TPW4020DQ integrates comprehensive diagnostic and protection features, including overcurrent/short-circuit current limiting, absolute and rate-of-change thermal shutdown, output open-circuit detection, ground- and power-supply-loss protection, and overvoltage/undervoltage protection. In practical applications, it serves a triple role: high-power load driver, system-status monitor, and fault-risk fuse.

The TPW4020DQ is the ideal choice for applications that demand the highest levels of reliability and safety, with use cases spanning the following areas:

1. Thermal Management and Chassis Control for New Energy Vehicles

It is designed for direct drive of electronic water pumps, electronic oil pumps, active suspension solenoid valves, and other similar applications. The TPW4020DQ features a peak current rating of 70 A with current-limiting capability to handle inrush currents during startup; latch protection ensures rapid fault isolation; and high-precision current monitoring supports condition monitoring and predictive maintenance, thereby safeguarding thermal management and driving safety.

2. New Energy Vehicle PDU and Intelligent Power Distribution

In the regional controller, the PTC heater and blower are driven, and the TPW4020DQ features reverse-polarity protection for the power supply, which helps prevent module damage caused by assembly errors and enhances system fault tolerance.

3. Industrial Servo Drives and Robot Joint Control

It is used to power brakes, holding brake coils, and similar applications. The TPW4020DQ’s outstanding ability to withstand back EMF and its robust short-circuit endurance ensure absolute reliability for emergency-stop and hold functions, thereby protecting both equipment and personnel.

4. High-End Power Supplies and Energy Infrastructure

Serves as an intelligent solid-state switch in UPS systems and server power supplies. Ultra-low losses enhance efficiency, precise current monitoring enables load management and fault localization, and robust protection ensures rapid fault isolation.

In complex operating environments, certain fault conditions place even more stringent demands on the high-side switch itself. Figure 3 illustrates a hard short fault with a 4.7 µH inductor (AEC-Q100-012), in which the current-limiting protection is triggered, resulting in a peak switch current of up to 73 A. Subsequently, the thermal-gradient protection mechanism is activated (shutting off the power switch), and the inductor’s freewheeling current causes the VDS voltage across the power switch to reach the clamping voltage (close to 40 V). During the clamping event, the maximum current can exceed 50 A, and the extremely high instantaneous power poses a severe challenge to the reliability of the high-side switch.

In Figure 3, the TPW4020DQ starts timing immediately after a short-circuit fault occurs and continuously retries via the temperature-gradient protection mechanism. Once the retry timer TRetry is reached, the switch is completely turned off to protect the associated application.

Figure 3: Output short-circuit test with a 4.7 µH hard short

The TPW4020DQ features a unique fault retry and latch protection mechanism that enables intelligent power lockout, allowing it to support applications with larger capacitive loads. Figure 4 shows the TPW4020DQ’s multiple retry cycles, which are controlled by its internal current-limiting and thermal protection functions, successfully achieving normal power-up with a 4.7 mF capacitor at the output. In contrast, under the same conditions, the power-up waveform of a comparable foreign competitor with a 4.7 mF capacitor is shown in Figure 5.

Figure 4: Power-up of the TPW4020DQ output with a 4.7 mF capacitor

Figure 5: Power-up with a 4.7 mF capacitor at the output of Competitor A

The launch of the TPW4020DQ represents a pivotal move by Silipu in the high-end intelligent high-side switch segment, precisely addressing the market’s urgent demand for domestically produced power devices that offer high reliability and high integration. It underscores Silipu’s commitment to driving growth through technological innovation and its deep engagement in the automotive and industrial core markets.

 

Currently, Silipu has launched several automotive-grade high-side driver chips:

TPS42Q20xQ: 40-V, 4-channel, 2-A-per-channel high-side switch with integrated fault detection and fault reporting.

TPS42S40xQ: 40V, single-channel, 4A high-precision current-sensing high-side switch;

TPW20400xQ: 15 V, 4/2 channels, 0.6 A per channel, I²C-compatible, high-side switch compliant with functional safety standards.