Offering low output voltage (0.8V min.) with excellent analog characteristics
such as 1% precision output voltage and high load stability
November 25, 2009
New Japan Radio releases the NJM2841, 500mA output-current low output voltage LDO
November 25, 2009 - New Japan Radio Co., Ltd has introduced to the market, the NJM2841, 500mA output-current low output voltage LDO (Low Dropout voltage regulator), suitable for the power unit of CPU, DSP and ASIC*1.
[Background of development]
In digital Ics such as CPU, DSP and ASIC, the improving processing capability demands elements and layout shrinking, low voltage operating and also high operating current. Therefore, the power units for them are required high precision output voltage and high stability under load fluctuation.
To meet these needs, New Japan Radio Co., Ltd. has developed the NJM2841, 500mA output-current low output voltage LDO.
The NJM2841 is a dual power supply operation (sequence free type) LDO consists of constant-voltage circuit, ON/OFF control circuit, over-current protection circuit and thermal overload protection circuit.
- 1.Providing high precision output voltage and high load stability
- While offering low output voltage (0.8V min.), the NJM2841 also provides high precision output voltage (1.0%) and high load stability (load regulation 0.002%/mA max.), and features low noise (Vno=40µVrms typ.) and high ripple rejection ratio (86 dB typ.). So it has the analog characteristics suitable for the power unit of CPU, DSP and ASIC.
- 2.Dual power supply operation with sequence free
- In general voltage regulators, power supply for input voltage (VIN) and control circuit (VBIAS) are connected inside. So when input voltage is low, analog characteristics such as load stability etc are becoming worse due to control circuit's physical limitations. To clear up this problem, the NJM2841 employs dual power supply which has two inputs, VIN and VBIAS separately. Furthermore, dual power supply needs a strict control sequence, imposing constraints to circuit design. The NJM2841 employs the dual power supply without a complex control sequence (sequence free), reduces the burden of design.
- 3.Using small size 4.7 µF ceramic capacitor is available
- The NJM2841 has realized using ceramic capacitor as output capacitor, by circuit layout optimization. It provides the cost down and space saving of the mounted board.
- *1:ASIC (Application Specific Integrated Circuit)
||Io=500mA LDO ( Low Dropout Voltage Regulator )
||Power unit of CPU, DSP and ASIC (using in TV, Blu-ray Disc, DVD recorder and Car-audio etc)
[Features & Characteristics]
- Output Voltage Range 0.8V to 2.5V
- High ripple rejection ratio 86dB typ.(f=1kHz Vo=1.2V)
- Low noise VNO = 40µVrms typ.(Vo=1.2V)
- Maximum output current Io(max.)=500mA
- High precision output voltage Vo±1.0%
- Dual power supply operation(VIN , VBIAS / sequence free)
- High load stability load regulation = 0.002%/mA (max.)
- Using 4.7µF ceramic capacitor available
- ON/OFF Control
- Built-in thermal overload protection circuit
- Built-in over-current protection circuit
- Bipolar technology
- Package outline SOT-23-5(MTP5)(2.9×2.8×1.3mm)
- Engineering Samples(ES) : already available from October 2009
- Mass Production(MP) : already available from November 2009