Overview
The PM6686TR is a dual step-down controller designed by STMicroelectronics to provide high-efficiency power conversion. It is particularly suited for applications requiring multiple regulated output voltages, such as notebook computers, PDAs, mobile devices, and tablet PCs. The device features a constant ON-time control architecture, which ensures fast load transient response and nearly constant switching frequency operation. Additionally, it incorporates lossless current sensing and pulse skipping techniques to enhance efficiency at light loads.
Key Specifications
| Parameter | Value |
|---|---|
| Input Voltage Range | 5.5 V to 28 V |
| Output Voltages | Fixed: OUT1 = 1.5 V/5 V, OUT2 = 1.05 V/3.3 V; Adjustable: OUT1 = 0.7 V to 5.5 V, OUT2 = 0.7 V to 2.5 V |
| Output Voltage Accuracy | ± 1.5% over valley regulation |
| Switching Frequency | Selectable; minimum frequency in pulse skip mode: 33 kHz |
| Linear Regulator Output | Fixed: 3.3 V/5.0 V; Adjustable: 0.7 V to 4.5 V, up to 200 mA |
| Reference Voltages | 3.3 V ± 2.0%, 2.0 V ± 1.0%, 50 µA |
| Package | VFQFPN-32 5 x 5 mm |
Key Features
- Constant ON-time control for fast load transient response
- Lossless current sensing and programmable current limit
- Pulse skipping technique for increased efficiency at light loads
- Selectable switching frequency and minimum frequency in pulse skip mode
- Independent Power Good and EN signals
- Latched OVP and UVP protection
- Soft-start and soft-stop internally fixed at 2 ms
- Auxiliary charge pump controller
- Linear regulator with switchover function
Applications
- Notebook computers
- Main power supply (3.3 V/5 V), chipset power supply (1.5 V/1.05 V), DDR1/2/3, and graphic cards power supply
- PDAs, mobile devices, tablet PCs or slates
- 3-4 cells Li+ battery powered devices
Q & A
- What is the input voltage range of the PM6686TR?
The input voltage range is from 5.5 V to 28 V.
- What are the fixed output voltages available on the PM6686TR?
The fixed output voltages are OUT1 = 1.5 V/5 V and OUT2 = 1.05 V/3.3 V.
- Can the output voltages be adjusted?
- What is the accuracy of the output voltages?
The output voltage accuracy is ± 1.5% over valley regulation.
- What is the minimum switching frequency in pulse skip mode?
The minimum switching frequency in pulse skip mode is 33 kHz.
- Does the PM6686TR have built-in protection features?
- What is the package type of the PM6686TR?
The package type is VFQFPN-32 5 x 5 mm.
- What are the reference voltages provided by the PM6686TR?
The reference voltages are 3.3 V ± 2.0%, 2.0 V ± 1.0%, and 50 µA.
- Does the PM6686TR support soft-start and soft-stop?
- What is the purpose of the auxiliary charge pump controller?
The auxiliary charge pump controller can monitor an optional external charge pump.
