Overview
The A5973AD is a step-down monolithic power switching regulator designed by STMicroelectronics. It is capable of delivering up to 1.5 A DC current to the load, with a minimum switch current limit of 1.8 A. The device is packaged in an HSOP8 package with an exposed frame, which reduces the thermal resistance (Rth(JA)) to approximately 40 °C/W. This regulator is particularly suited for automotive applications due to its ability to operate with an input voltage as low as 4 V, making it compatible with cold crank conditions. The internal P-channel DMOS transistor with a typical RDS(on) of 250 mΩ minimizes the size of external components. The switching frequency is internally fixed at 500 kHz, and the device includes features such as pulse-by-pulse current limit and internal frequency modulation for effective short-circuit protection.
Key Specifications
| Parameter | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|
| Operating Input Voltage | 4 | - | 36 | V |
| Output Current | - | - | 1.5 | A |
| Reference Voltage | 3.2 | 3.3 | 3.399 | V |
| Switching Frequency | 425 | 500 | 575 | kHz |
| MOSFET On Resistance | 0.250 | - | 0.5 | Ω |
| Maximum Limiting Current | 1.8 | - | 2.3 | A |
| Operating Junction Temperature | -40 | - | 150 | °C |
| Thermal Resistance (Junction to Ambient) | - | - | 40 | °C/W |
Key Features
- Qualified following the AEC-Q100 requirements
- 1.5 A DC output current
- Operating input voltage from 4 V to 36 V
- 3.3 V / (± 2%) reference voltage
- Output voltage adjustable from 1.235 V to VIN
- Low dropout operation: 100% duty cycle
- 500 kHz internally fixed frequency
- Voltage feed-forward
- Zero load current operation
- Internal current limiting
- Inhibit for zero current consumption
- Synchronization
- Protection against feedback disconnection
- Thermal shutdown
Applications
The A5973AD is primarily dedicated to automotive applications, where it can operate effectively even in cold crank conditions. Its robust design and compliance with AEC-Q100 requirements make it suitable for a variety of automotive systems.
Q & A
- What is the maximum output current of the A5973AD?
The A5973AD can deliver up to 1.5 A DC current to the load.
- What is the operating input voltage range of the A5973AD?
The operating input voltage range is from 4 V to 36 V.
- What is the reference voltage of the A5973AD?
The reference voltage is 3.3 V with a ± 2% tolerance.
- What is the switching frequency of the A5973AD?
The switching frequency is internally fixed at 500 kHz.
- Does the A5973AD have thermal protection?
Yes, the device includes thermal shutdown protection.
- What is the typical RDS(on) of the internal P-channel DMOS transistor?
The typical RDS(on) is 250 mΩ.
- Can the output voltage be adjusted?
Yes, the output voltage can be adjusted from 1.235 V to VIN.
- Does the A5973AD support synchronization?
Yes, the device includes synchronization functionality.
- What is the thermal resistance (Rth(JA)) of the HSOP8 package?
The thermal resistance is approximately 40 °C/W.
- Is the A5973AD compliant with automotive standards?
Yes, it is qualified following the AEC-Q100 requirements.
