NCP690 - 1.0 A Very Low Dropout CMOS Linear Voltage Regulator
The NCP690/ NCP691 /NCP692 devices are designed to be Very Low Dropout (LDO) 1 Amp Linear Voltage regulators. This new CMOS VLDO family provides 1A of output current in either fixed voltage options or an adjustable output voltage from 5.0 V down to 1.25 V.
The devices are designed for space constrained and portable battery powered applications and offer many important features such as high PSRR, low Quiescent and Ground current consumption, low noise operation and short circuit and thermal protection. They offer enhanced ESD protection compared to standard CMOS LDOs and are designed to be used with low cost ceramic capacitors. The NCP691 includes an Enable low function, the NCP692 an enable high, and all three products are packaged in the 6-Lead DFN3x3 package.
Features & Benefits
Features: | Benefits: |
Output voltage options: Adjustable, 1.5 V, | Available in the most popular voltage options. Others may be available on request. |
Current limit protection | Leads to more robust products |
Thermal shutdown protection | Suitable for use in harsh environments |
Typical noise voltage of 15 Vrms without a bypass capacitor | Suitable for audio and other electrical noise sensitive applications |
Input voltage down to 1.5 V | Suitable for lower voltage input rails |
Typical dropout voltage of 190 mV at 1 A (Vout = 2.5 V, TJ = 25C) | Suitable for lower voltage input rails and battery powered applications |
Active low enable pin (NCP691 device) | Power saving modes |
Enhanced ESD: 4 kV and 400 V | Less inclined to damage during board assembly compared to standard CMOS devices. |
Active output discharge | Faster response time to shutdown and less chance of damaging reverse current flows |
Guaranteed 1 A output current | |
2% output voltage tolerance over all operating conditions (fixed output options) | |
Adjustable output by external resistors from 5.0 V down to 1.25 V | |
1.5% output voltage tolerance over all operating conditions (adjustable) |
Applications
- DSP, FPGA, microprocessor power supplies
- SMPS post-regulator
- Modem banks, routers, telecom boards, computer and game box accessories
- Car entertainment systems, battery powered applications
- Cable boxes, satellite receivers, set top boxes
End Products
- Laptops and PCI cards
- Hard disk drivers
Evaluation Board Description
The NCP690 CMOS LDO family provides 1 A of output current with enhanced ESD in fixed output voltage options from 1.5 V to 5.0 V. These devices are designed for space constrained and portable battery powered applications and offer additional features such as low Dropout Voltage, high Power Supply Rejection Ratio (PSRR), low Quiescent and Ground Current consumption, low Noise operation, Short Circuit and Thermal Protection. NCP690 is designed to be used with low cost ceramic capacitors and the minimum value of 1µF output capacitance is required. The NCP690 device is equipped with Active Output Discharge, Current Limit and Thermal Shutdown Protection. Finally the Surface Mount DFN3x3 package with Expose Pad allows saving PCB space and effectively dissipating heat through the PCB copper area.
This demonstration board operates from a dc input voltage VIN < 6 V and produces fixed output voltage given by the NCP690 internal voltage divider.
