LDO_51 IP Library: High PSRR, Low power, 80mA Low Dropout Voltage Regulator PRODUCT PREVIEW ■ ANALOG BASEBAND REGULATOR ■ VERY LOW DROPOUT VOLTAGE : 50mV APPLICATION NOTE An external capacitor (COUT = 1µF) with an equivalent serial resistance (ESR) in the range 0.02 to 0.6Ω is used for regulator stability. ■ HIGH PSRR : 60dB ■ LOW QUIESCENT CURRENT : 130µA Figure 1 : Block Diagram ■ LOW OUTPUT VOLTAGE NOISE ■ NO CURRENT IN POWER DOWN MODE IN ? PWRDWN ? ■ SHORT CIRCUIT PROTECTION ? OUT ■ SMALL DECOUPLING CERAMIC CAPACITOR TYPICAL APPLICATIONS – Cellular and Cordless phones supplied by 1 cell Lithium-ion battery / 3 cells Ni-MH or Ni-Cd battery. VREF – PDA (Personal Digital Assistant), Smart phone. – Portable equipment. – Supply for Analog and Mixed-signal devices for cellular phone. LDO_51 Figure 2 : Typical Application Circuit VIN Power Down Mode IN PWRDWN ? ? OUT VOUT 1µF ? COUT LDO_51 ON ESR OFF ? GND June 2002 This is advance information on a new product now in development or undergoing evaluation. Details are subject to change without notice. 1/4 LDO_51 ELECTRICAL CHARACTERISTICS 3V < VIN < 5.5V, -55°C < TA < +125°C, VREF = 2.8V, 0.8µF < COUT < 1.2µF, 20mΩ < ESR < 0.6Ω. 100µA < ILOAD < 80mA. Typical case : VIN = 4V, T = 25°C, IOUT = 40mA. Parameter Input Voltage Range (Note 1) Output Voltage Symbol Test Condition VIN Min 3 Output Voltage Accuracy IOUT PMOS Output Resistance RON Dropout Voltage ∆VDO Max Unit 5,5 V 2,8 VOUT Output current Typ V -3 3 % 0,1 80 mA 0,5 Ω 50 mV µA ∆VOUT = 50mV, ILOAD = 80mA (Note 2) Quiescent current Power down mode IQ 170 ILOAD = 100µA 30 50 ILOAD = 80mA 130 170 IQPDM Power down active 100 nA PSRR f < 10KHz 50 60 dB f < 100KHz 40 50 quiescent current Power Supply Rejection Ratio Line Regulation Lir ILOAD = 80mA, 3 6 mV 30 45 mV 1 mV 1 mV VIN = 3V to 5.1V Load Regulation Ldr Line Transient Lirt ∆VIN = 300mV tRISE = tFALL = 10µs Load Transient Ldtr 10% to 90% and 90% to 10% of 80mA in 10µs Output Noise Voltage en 100Hz 1,5 µV -----------Hz 1KHz 550 100KHz 300 nV -----------Hz Output decoupling Capacitor COUT Settling time Short Circuit Current Limit From power down to active mode ISHORT µF 1 180 230 25 µs 300 mA Notes: 1. Above characteristics are given for 3V minimum input operating range voltage, but regulator is operational with 2.7V minimum input voltage. 2. All parameters are guaranteed with 170mV Dropout voltage. 2/4 LDO_51 TYPICAL CHARACTERISTICS Figure 3 : Line transient Figure 4 : Settling Time Figure 5 : Load Transient (rising edge) Figure 6 : Load Transient (falling edge) Figure 7 : PSRR vs Frequency (ILOAD max - VIN min) Figure 8 : Noise vs Frequency (ILOAD max - VIN min) 60 650 600 550 500 50 NOISE (nVrms) NOISE (nVrms) 450 40 400 350 300 250 200 30 150 100 50 20 100 1000 FREQUENCY (Hz) 10000 100000 0 100 1000 10000 100000 FREQUENCY (Hz) 3/4 LDO_51 Figure 9 : Current Consumption vs Output Current (VIN = 4V) CURRENT CONSUMPTION (µA) 120 100 80 60 40 20 0.02 0.1 10 20 30 40 50 60 70 80 OUTPUT CURRENT (mA) Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics © 2002 STMicroelectronics - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - United States http://www.st.com 4/4