Overview
The LM2660, produced by Texas Instruments, is a versatile CMOS charge-pump voltage converter that operates as either a switched capacitor inverter or a voltage doubler. This device is designed to provide efficient voltage conversion without the need for inductors, thereby reducing cost, size, and electromagnetic interference (EMI). It can operate over a wide input voltage range of 1.5 V to 5.5 V and is suitable for various battery-powered systems due to its low operating current of 120 µA and high efficiency greater than 90% at most loads.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Unit |
|---|---|---|---|---|
| Supply Voltage (V+ to GND) | 1.5 | - | 5.5 | V |
| Output Current (V+ and OUT continuous) | - | - | 120 | mA |
| Output Resistance (IL = 100 mA) | - | 6.5 | - | Ω |
| Conversion Efficiency at 100 mA | - | 88% | - | % |
| Oscillator Frequency (FC = Open) | - | 10 kHz | - | kHz |
| Oscillator Frequency (FC = V+) | - | 80 kHz | - | kHz |
| Operating Junction Temperature | -40 | - | 85 | °C |
Key Features
- Inverts or doubles the input supply voltage using two low-cost external capacitors.
- Operates over a wide input voltage range of 1.5 V to 5.5 V.
- Selectable oscillator frequency: 10 kHz or 80 kHz, with the option to use an external oscillator input up to 150 kHz.
- Typical output resistance of 6.5 Ω and conversion efficiency of 88% at 100 mA.
- Narrow SOIC and VSSOP packages available.
- Low operating current of 120 µA and high efficiency greater than 90% at most loads.
- Optional external oscillator input and frequency control pin.
Applications
- Laptop computers
- Cellular phones
- Medical instruments
- Operational amplifier power supplies
- Interface power supplies
- Handheld instruments
Q & A
- What is the input voltage range of the LM2660?
The LM2660 operates over an input voltage range of 1.5 V to 5.5 V.
- What are the typical applications of the LM2660?
The LM2660 is commonly used in laptop computers, cellular phones, medical instruments, operational amplifier power supplies, interface power supplies, and handheld instruments.
- How does the LM2660 achieve voltage inversion or doubling?
The LM2660 uses two external capacitors and four large CMOS switches to invert or double the input supply voltage.
- What is the typical output resistance of the LM2660?
The typical output resistance of the LM2660 is 6.5 Ω.
- Can the LM2660 be driven by an external oscillator?
Yes, the LM2660 can be driven by an external oscillator input up to 150 kHz.
- What is the maximum output current of the LM2660?
The maximum continuous output current of the LM2660 is 120 mA.
- How efficient is the LM2660 in terms of power conversion?
The LM2660 has a typical conversion efficiency of 88% at 100 mA.
- What are the available package types for the LM2660?
The LM2660 is available in narrow SOIC and VSSOP packages.
- What is the operating junction temperature range of the LM2660?
The operating junction temperature range of the LM2660 is from -40°C to 85°C.
- How does the LM2660 handle low input voltages?
For input voltages less than 3.5 V, the LV pin must be connected to ground to bypass the internal regulator circuitry for optimal performance.
