Overview
The STLD40D, produced by STMicroelectronics, is a boost converter specifically designed for powering white LEDs in various applications, particularly for LCD backlighting. This device operates within an input voltage range of 3.0 V to 5.5 V and can generate an output voltage as high as 37 V, capable of driving up to 10 white LEDs in series. It features a pulse frequency modulation (PFM) mode and operates in discontinuous conduction mode (DCM). The STLD40D is known for its high efficiency, adjustable peak inductor current limit, and low shutdown current, making it suitable for mobile and handheld devices.
Key Specifications
| Parameter | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|
| Input Voltage Range (VI) | 3.0 | - | 5.5 | V |
| Output Voltage Range (VO) | VI | - | 37 | V |
| Regulated Output Current (IO) | - | 20 | - | mA |
| Stand-by Current (ISD) | 1 | 3 | - | µA |
| Quiescent Current (IQ) | 0.4 | 0.8 | 1.2 | mA |
| Boost Switch RDSON | 0.4 | - | 0.5 | Ω |
| Maximum Peak Inductor Limit (ILIM) | 0.75 | 1.1 | - | A |
| Feedback Voltage (VFB) | 130 | 165 | 200 | mV |
| Over Voltage Protection (OVP) | 36 | - | 42 | V |
| Operating Temperature (TOP) | -40 | - | 85 | °C |
Key Features
- Inductor switch boost controller operating in PFM mode
- High efficiency over a wide range of input voltage (3.0 V to 5.5 V)
- Over voltage protection with automatic restart
- Adjustable peak inductor current limit
- Enable pin with possibility of PWM dimming control
- Low shutdown current (< 1 µA)
- Small external component count
- Good load and line regulation
- Compact QFN8 3 x 3 mm package
Applications
- White LED supply for LCD backlight
- Mobile phones
- PDA and organizers
- Any handsets powered from 3.0 V to 5.5 V
Q & A
- What is the input voltage range of the STLD40D?
The input voltage range of the STLD40D is from 3.0 V to 5.5 V.
- What is the maximum output voltage the STLD40D can provide?
The STLD40D can provide an output voltage as high as 37 V.
- How many white LEDs can the STLD40D drive in series?
The STLD40D can drive up to 10 white LEDs in series.
- What is the typical regulated output current of the STLD40D?
The typical regulated output current is 20 mA at an output voltage of 36 V.
- Does the STLD40D have over voltage protection?
- How can the peak inductor current limit be adjusted?
The peak inductor current limit can be adjusted by connecting a resistor to the RSET pin.
- What is the purpose of the ENABLE pin?
The ENABLE pin allows turning the controller on/off and can be used for PWM dimming control.
- What is the typical standby current of the STLD40D?
The typical standby current is 3 µA when the enable pin is low.
- What is the package type and size of the STLD40D?
The STLD40D comes in a QFN8 package with dimensions of 3 x 3 mm.
- What are some common applications of the STLD40D?
