Transcript
Ultra-High Voltage Linear Voltage Regulator Family - Introduction •
Innovation 10mA, Ultra-High Input Voltage, Very-Low IQ Linear Voltage Regulator Family for converting high input voltage i.e. AC line voltage (80 VAC – 260 VAC) down to a low-voltage rail suitable for the MCUs, Touch Sensor Controllers i.e. 3.3V, 5V, 12V
• Value Advantage Comparing to Non-Isolated SMPS or Capacitive Dropper: Provides Smaller Solution Size Allows to Lower the Solution Cost Assures Lower Output Noise and Better Accuracy Improves Standby Power Consumption
1 LDO Update, January 2014
NCP785A – Very Wide Input Voltage Range Linear Voltage Regulator Value Proposition The NCP785A is high-performance linear regulator, offering a very wide operating input operating voltage range of up to 450V DC, with an output current of 10mA. The NCP785A offer ±5% accuracy, extremely high-power supply rejection ratio and ultra-low quiescent current. The NCP785A is optimized for high-voltage inputs, making it ideal for harsh environment applications.
Unique Features • • • • • •
24V to 450V operating VIN 700V Maximum VIN PSRR: 80 dB at 120 Hz Quiescent Current: 15µA typ. SOT89 package Directly converts the AC voltage down to low-voltage DC.
Benefits • • • • • •
Allows for direct AC mains operation VIN Immune against the VIN spikes 85-265VAC Effectively reduces the input ripple Greatly reduces power consumption 2.2µF Ideal for tiny space Considerably simplifies the Power Supply design
Other Features • • • • •
Application Data
Guaranteed Output Current of 10mA Fixed Output Voltage Options Available: 3.3V, 5.0V, 12V, 15V ±5% Accuracy Over Line and Temperature Over-current and Short-Circuit Protection Thermal Shutdown Protection
VOUT 5V IN
OUT GND
10µF
Ordering & Package Information Part Number
Output Voltage
Marking
Package
NCP785AH33T1G
3.3V
AA
SOT89-3
NCP785AH50T1G
5.0V
AC
SOT89-3
NCP785AH120T1G
12V
AE
SOT89-3
NCP785AH150T1G
15V
AD
SOT89-3
Market & Applications • Industrial, Home Automation, White Goods, Lighting • Low-Power MCU Applications Power Supply • Smaller Size, No-Load Efficient replacement for Capacitive Dropper 2 LDO Update, January 2014
SOT89-3 package
• Evaluation Boards Available
Comparison of NCP785A vs. Capacitive Dropper Voltage Regulator Solutions •
Value proposition o
Benefits of NCP785A over the capacitive dropper solution NCP785A based AC/DC power supply
Capacitive dropper AC/DC power supply
NCP785A
Typical Application Diagram
VIN 230V AC
CIN 2.2uF/450V
GND
COUT 22uF/6.3V
3.24mW
Real No Load Power Solution Cost Estimation
VOUT 5V @ 10mA
VOUT
VIN
VOUT 5V @ 10mA
X1 COUT 220uF/6.3V
≥ 90mW
(324V * 10µA) NCP785A IC, SOT89-3 Cap. 2.2uF/450V Alu ±20% Rect. Diode, 1A, 1000V, DO-41 (x1) Cap. 22uF/6.3V Cer. ±20%
VIN 230V AC
CSER 220nF/630V
80%
(losses dependent on zener current, series resistor) Cap. X1 type, 275VAC, 0.22µF Zener Diode 5.1V, 0.5W, SOD123 Res. 470Ohm, 0.5W, 1210 ±5% 100% Rect. Diode, 1A, 1000V, DO-41 (x2) Cap. 220uF/6.3V Alu ±20%
Output Accuracy
±5%
Solution Size
≥ 50%
Output Noise
0.1%
100%
(PSRR = 80dB @ 100Hz, Noise = 240uVrms)
(Output ripple of 200mV - 300mV when loaded)
Yes - Full
Yes – But Limited
(Thermal, Overcurrent)
(Overcurrent)
Protection
3 LDO Update, January 2014
>±5% (AC mains ripple at the output)
100% (X1 Cap. occupying large PCB space)
Comparison of NCP785A vs. Discrete Transistor Voltage Regulator Solutions •
Value proposition o Benefits of NCP785A over the discrete regulator in HV DC application NCP785A based HV DC power supply
Discrete HV DC power supply VIN (DC)
VIN (DC) VCC NCP785A
Typical Applications Diagram
VIN
VOUT
VCC GND COUT 10uF/25V COUT 10uF/25V
3.24mW
Real No load Power Solution Cost
64mW
(324V * 10µA) NCP785A IC, SOT89-3 Cap. 10uF/25V Cer. ±20%
85%
Output Accuracy
±5%
Solution Size
≥ 40%
Protection
Yes - Full
4 LDO Update, January 2014
(Thermal, Overcurrent)
(324V * 200µA) Transistor SOT-23, 0.5W, 600W Zener Diode 5.1V, 0.5W, SOD123 Shottky Diode, 1A, 100V, DO-41 Cap. 10uF/25V Cer. ±20% Res. 0.5W, 1210 ±5% (x3)
≥ ±5% (Output voltage is: VZ – UBE – VD)
100%
(Needs at least external 5 components)
No
100%
NCP785A main benefits summary Solution size
→
NCP785A features smaller solution size. Allows for shrinking the PCB size.
Solution cost
→
NCP785A offers slightly smaller solution cost with important additional benefits.
Component count
→
Replaces at least 5 discrete components – improves reliability.
Lower No-load power
→
Draws ~10 times less power than the discrete solution. Helps to meet the extending no-load power requirements.
Output accuracy
→
Better accuracy - Saves additional post regulator cost in case that precise output voltage is required.
Output noise
→
Generates very small output noise. Allows to supply noise sensitive circuits without the need for additional filtering
5 LDO Update, January 2014
