Overview
The LM2733YMF is a high-frequency switching boost regulator produced by Texas Instruments (formerly National Semiconductor). This device operates at a fixed frequency of 600 kHz and is designed for applications requiring high output voltages and compact size. The LM2733YMF features a 40-V internal DMOS FET switch, enabling switch currents up to 1 A and supporting a wide input voltage range from 2.7 V to 14 V. The device is packaged in a 5-pin SOT-23 package, making it ideal for space-constrained designs.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Switching Frequency | 0.40 | 0.60 | 0.80 | MHz |
| Maximum Duty Cycle | 93% | 96% | - | % |
| Input Voltage Range | 2.7 | - | 14 | V |
| Switch Current | - | 1 | - | A |
| Shutdown Current | - | < 1 µA | - | µA |
| Package Type | - | SOT-23 (5-pin) | - | - |
| Operating Temperature Range | -40 | - | 125 | °C |
Key Features
- 40-V internal DMOS FET switch
- Fixed switching frequency of 600 kHz (Y option)
- Low RDS(ON) DMOS FET
- Switch current up to 1 A
- Wide input voltage range: 2.7 V to 14 V
- Low shutdown current (< 1 µA)
- 5-Pin SOT-23 package for high power density
- Uses tiny capacitors and inductors
- Cycle-by-cycle current limiting and thermal shutdown protection
- Internally compensated for simplified design
Applications
- White LED current source
- PDAs and palm-top computers
- Digital cameras
- Portable phones and games
- Local boost regulator in various portable devices
Q & A
- What is the switching frequency of the LM2733YMF?
The LM2733YMF operates at a fixed switching frequency of 600 kHz.
- What is the maximum switch current of the LM2733YMF?
The maximum switch current is up to 1 A.
- What is the input voltage range of the LM2733YMF?
The input voltage range is from 2.7 V to 14 V.
- How does the shutdown feature work on the LM2733YMF?
The device is turned off by pulling the shutdown pin low. If this feature is not used, the pin should be tied directly to VIN.
- What type of protection does the LM2733YMF offer?
The device offers cycle-by-cycle current limiting and thermal shutdown protection.
- What kind of capacitors are recommended for use with the LM2733YMF?
Multi-layer ceramic capacitors with X5R and X7R dielectric types are recommended.
- What is the typical application circuit for the LM2733YMF?
A typical application circuit involves a boost converter configuration with external resistive dividers, capacitors, and inductors. See the datasheet for detailed design procedures.
- How does the LM2733YMF handle thermal considerations?
The device's thermal performance is affected by the duty cycle and power dissipation within the FET switch. Proper thermal management is necessary to ensure reliable operation.
- What are some common applications for the LM2733YMF?
Common applications include white LED current sources, PDAs, digital cameras, portable phones, and games.
- What is the package type of the LM2733YMF?
The device is packaged in a 5-pin SOT-23 package.
