LDO_52 IP Library: High PSRR, Low Power, 70mA Low Dropout Voltage Regulator PRODUCT PREVIEW ■ DIGITAL BASEBAND REGULATOR ■ VERY LOW DROPOUT VOLTAGE : 50mV APPLICATION NOTE An external capacitor (COUT = 1µF typical) with an equivalent serial resistance (ESR) in the range 0.02 to 0.6Ω is used to ensure stability. ■ HIGH PSRR : 60dB ■ LOW QUIESCENT CURRENT : 150µA Figure 1 : Block Diagram ■ 1µA STAND-BY MODE CURRENT ■ NO CURRENT IN POWER DOWN MODE IN ? PWRDWN ? STDBY ? ■ SHORT CIRCUIT PROTECTION ■ SMALL DECOUPLING CERAMIC CAPACITOR ? OUT 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 Digital (Memory, DSP/Microcontroller) devices. LDO_52 Figure 2 : Typical Application Circuit IN VIN Power Down Mode ON OFF PWRDWN ? Stand-by Mode → → Active Mode OUT VOUT 1µF ? → → Stand-by Mode ? COUT LDO_52 ESR 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_52 ELECTRICAL CHARACTERISTICS 3V < VIN < 5.5V, -30°C < T < +125°C, VREF = 2.8V, 0.8µF < COUT < 1.2µF, 20mΩ < ESR < 0.6Ω. 100µA < ILOAD < 70mA. Typical case : VIN = 4V, T = 25°C, IOUT = 35mA. Parameter Input Voltage Range (Note 1) Output Voltage Symbol Test Condition VIN Typ 3 VOUT -3 IOUT PMOS Output Resistance RON Dropout Voltage ∆VDO Max Unit 5,5 V 2,8 Output Voltage Accuracy Output current Min V 3 % Active mode 70 mA Low power mode 500 µA 0,2 Ω 60 mV µA ∆VOUT = 50mV, ILOAD = 70mA (Note 2) Quiescent current Stand-by current IQ ISTDBY Power down mode quiescent current IQPRWDWN Power Supply Rejection Ratio PSRR 170 ILOAD = 100µA 20 30 ILOAD = 70mA 150 170 ILOAD = 500µA 5 10 µA 100 1000 nA Power down active DC 50 60 f < 10KHz 40 45 dB Load Regulation Ldr VOUT = 2.8V 20 35 mV Line Regulation Lir ILOAD = 70mA, 2 3 mV 10 mV 3 mV 5 mV 6 µs VOUT = 2.8V Std-by mode ILOAD = 500µA Line Transient Lirt VOUT = 2.8V ILOAD = 70mA, ∆VIN = 300mV, tRISE = tFALL = 10µs Load Transient Ldtr 10% to 90% and 90% to 10% of 70mA in 10µs Recovery time Output decoupling capacitor C OUT µF 1 Settling time VOUT = 2.8V, (from power down to active mode) COUT = 1µF Short Circuit Current Limit 5 ISHORT 20 300 50 µs 800 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_52 TYPICAL CHARACTERISTICS Figure 3 : Line transient (ILOAD = 35mA ; VBAT = 4V + 300mV with 10µs) Figure 4 : Line transient (ILOAD = 35mA ; VBAT = 4V + 300mV with 10µs) Figure 5 : Load transient (ILOAD = 0 to 70mA ; VBAT = 4V) Figure 6 : Load transient (ILOAD = 0 to 70mA ; VBAT = 4V) Figure 7 : Settling Time 3/4 LDO_52 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