LDO57

LDO_57 IP Library: High Output Current, Low power, 400mA Low Dropout Voltage Regulator PRODUCT PREVIEW s DIGITAL BASEBAND REGULATOR s VERY LOW DROPOUT VOLTAGE : 50mV s HIGH OUTPUT CURRENT : 400mA s LOW QUIESCENT CURRENT : 100µA s HIGH PSRR : 60dB s LOW OUTPUT VOLTAGE NOISE s NO CURRENT IN POWER DOWN MODE s SHORT CIRCUIT PROTECTION TYPICAL APPLICATIONS – Cellular and Cordless phones supplied by 1 cell Lithium-ion battery / 3 cells Ni-MH or Ni-Cd battery. – PDA (Personal Digital Assistant), Smart phone. – Portable equipment. – Supply for Digital Baseband devices for cellular phone. Figure 2 : Typical Application Circuit IN APPLICATION NOTE An external capacitor (COUT = 4.7µF) with an equivalent serial resistance (ESR) in the range 0.02 to 0.6Ω is used for regulator stability. Figure 1 : Block Diagram IN ? ? OUT PWRDWN STDBY ? ? VREF LDO_57 VIN ? ? OUT VOUT Power Down Mode ON OFF Stand-by Mode Stand-by Mode → → Active Mode → → PWRDWN 4.7µF ? LDO_57 ESR COUT STDBY ? ? 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_57 ELECTRICAL CHARACTERISTICS 3V < VIN < 5.5V, -30°C < TA < +85°C, VREF = 2.8V, COUT = 4.7µF ±20%, 20mΩ < ESR < 0.6Ω, ILOAD = 400mA. Typical case : VIN = 4V, T = 25°C, C OUT = 4.7µF, ILOAD = 400mA. Parameter Input Voltage Range (Note 1) Output Voltage Output Voltage Accuracy Output current Dropout Voltage IOUT ∆VDO ∆VOUT = 50mV, ILOAD = 400mA, (Note 2) Quiescent current IQ ILOAD = 100µA ILOAD = 40mA ILOAD = 400mA Power down mode quiescent current Power Supply Rejection Ratio IQPDM PSRR Power down active DC f = 10KHz Line Regulation Load Regulation Line Transient Load Transient Output Noise Voltage Lir Ldr Lirt Ldtr en ILOAD = 400mA, VIN = 2.9V to 5.5V ILOAD = 100µA - 400mA ∆VIN = 300mV tRISE = tFALL = 10µs ILOAD = 100µA - 400mA in 10µs 100Hz 1KHz 10KHz enRMS Output decoupling Capacitor Settling time Short Circuit Current Limit ISHORT COUT From power down to active mode BW : 100Hz to 100KHz 4,7 50 2 50 2,5 3 40 40 170 100 150 350 100 60 55 4 55 5 5 1,2 400 140 35 mV mV mV mV µV ----------Hz nV ----------Hz µVRMS µF µs A 150 230 450 nA dB Symbol VIN VOUT Test Condition Min 2,9 1,8 3 400 50 Typ Max 5,5 4,9 Unit V V % mA mV mV µA Notes: 1. Above characteristics are given for 2.9V minimum input operating range voltage, but regulator is operational with 2.7V minimum input voltage. 2. All performances of the regulator are guarenteed for a voltage drop of 170mV minimum. 2/4 LDO_57 ELECTRICAL CHARACTERISTICS : (Stand-by mode) 3V < VIN < 5.5V, -30°C < TA < +85°C, VREF = 2.8V, COUT = 4.7µF ±20%, 20mΩ < ESR < 0.6Ω, ILOAD = 500µA. Typical case : VIN = 4V, Ambient temperature, ILOAD = 500µA. Parameter Output current in stand-by mode Quiescent Current in stand-by mode Power Supply Rejection Ratio in stand-by mode Line Regulation in stand-by mode Load Regulation Symbol IOUTSTDBY ISTDBY PSRRSTY LirSTDBY Ldr STDBY ILOAD = 500µA f = 10KHz ILOAD = 500µA, VIN = 2.9V to 5.5V ILOAD = 100µA - 500µA 50 55 mV 35 20 45 2 6 Test Condition Min Typ Max 500 30 dB mV Unit µA TYPCIAL CHARACTERISTICS Figure 7 : PSRR vs Frequency for Various Voltage Drop -20 -30 PSRR (dB) -40 150m V -50 170m V 200m V -60 2V -70 1 10 100 1000 10000 100000 1000000 FREQUENCY (Hz) 3/4 LDO_57 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