Overview
The LM2734YMKX/NOPB is a high-frequency, PWM step-down DC/DC converter manufactured by Texas Instruments. This monolithic regulator is packaged in a 6-pin Thin SOT (SOT-23-THN) package, making it ideal for applications requiring minimal board space. The device supports a wide input voltage range of 3 V to 20 V and can deliver an output voltage from 0.8 V to 18 V with a maximum output current of 1 A. The LM2734YMKX/NOPB features internal compensation, current-mode control, and a high switching frequency, allowing for efficient operation with small surface-mount components.
Key Specifications
| Parameter | Min | Typical | Max | Unit |
|---|---|---|---|---|
| Input Voltage Range | 3 | 20 | V | |
| Output Voltage Range | 0.8 | 18 | V | |
| Output Current | 1 | A | ||
| Switching Frequency (LM2734X) | 1.2 | 1.6 | 1.9 | MHz |
| Switching Frequency (LM2734Y) | 0.40 | 0.55 | 0.66 | MHz |
| Switch ON Resistance | 300 | 600 | mΩ | |
| Quiescent Current (Switching) | 1.5 | 2.5 | mA | |
| Quiescent Current (Shutdown) | 30 | nA | ||
| Shutdown Current | 30 | nA | ||
| Internal Voltage Reference | 0.784 | 0.8 | 0.816 | V |
| Thermal Shutdown Temperature | 165 | °C |
Key Features
- Thin SOT-6 package for minimal board space
- Wide input voltage range: 3 V to 20 V
- Output voltage range: 0.8 V to 18 V
- High switching frequencies: 550 kHz (LM2734Y) and 1.6 MHz (LM2734X)
- Internal 300-mΩ NMOS switch
- Ultra-low shutdown current: 30 nA
- Internal soft start to reduce inrush current
- Current-mode control and internal compensation
- Pulse-by-pulse current limit and thermal shutdown
- Output overvoltage protection
- External shutdown control via enable pin
Applications
- Local point-of-load regulation
- Core power in hard disk drives (HDDs)
- Set-top boxes
- Battery-powered devices
- USB powered devices
- DSL modems
- Notebook computers
Q & A
- What is the input voltage range of the LM2734YMKX/NOPB?
The input voltage range is from 3 V to 20 V.
- What are the available switching frequencies for the LM2734?
The switching frequencies are 550 kHz for the LM2734Y and 1.6 MHz for the LM2734X.
- What is the maximum output current of the LM2734YMKX/NOPB?
The maximum output current is 1 A.
- What is the typical quiescent current in shutdown mode?
The typical quiescent current in shutdown mode is 30 nA.
- Does the LM2734YMKX/NOPB have internal overvoltage protection?
Yes, it has output overvoltage protection that turns off the internal NMOS switch if the output voltage exceeds 10% above the internal reference voltage.
- What is the purpose of the soft start feature in the LM2734YMKX/NOPB?
The soft start feature forces the output voltage to increase at a controlled rate during startup, reducing inrush current.
- How does the thermal shutdown feature work?
The thermal shutdown feature turns off the output switch when the IC junction temperature exceeds 165°C and remains off until the temperature drops to approximately 150°C.
- What types of capacitors are recommended for use with the LM2734YMKX/NOPB?
Surface-mount capacitors such as Sanyo POSCAP, Tantalum or Niobium, Panasonic SP, Cornell Dubilier ESR, and multilayer ceramic capacitors (MLCC) with X7R or X5R dielectrics are recommended.
- Can the LM2734YMKX/NOPB be used in battery-powered devices?
Yes, it is suitable for battery-powered devices due to its high efficiency and low quiescent current.
- How is the enable pin used in the LM2734YMKX/NOPB?
The enable pin controls the shutdown mode. When a logic low voltage is applied to the enable pin, the device enters shutdown mode, reducing the quiescent current to 30 nA.
