YB1231 HV600mA, Low-Noise LDO Regulator Description The YB1231 is a series of ultra-low-noise, low dropout (LDO) linear regulators with 2.0% output voltage accuracy. The YB1231 regulators achieve a low 440mV dropout at 600mA load current of 4.5V output and are available in voltages ranging from 3.2V to 4.5V with 0.1 V per step (custom voltage is considerable at request). The YB1231 regulators are optimized to work with low-ESR and low cost ceramic capacitors, reducing the amount of board space critical in hand-held devices. The YB1231 requires only 2.2μF output capacitor for stability with any load and consumes less than 1μA in shutdown mode. Built-in thermal shutdown and short-circuit protect offer secure protection against fault operation. The YB1231 regulators are available in SOT-23 / SOT-25 / SOT-89 packages. Features 2.0% Accuracy Output Voltage Output Voltage Range 3.2V ~ 4.5V Low-Noise Low-Drop-Out Stable with 2.2μF Ceramic Capacitor for Any Load Typical Output Current : 600mA Low Quiescent Current : ~100μA 440mV Dropout at 600mA Load (4.5V) Only Need Input and Output Capacitors Power Saving Shutdown Mode (<1μA) Thermal Protection Shutdown Built-In Internal Soft-Start Output Short-circuit Current Limit Protection Green package (RoHS) available Applications PDA, Palmtops and Notebook Computers DSC, Handset Camera Modules PCMCIA Cards, PC Cameras USB Based Portable Devices (MP3, PMP) GSM/GPRS/3G RF Transceiver Modules Wireless LANs Bluetooth Portable Radios Typical Application Circuit Figure 1-1: SOT-25 Application Circuit YB1231 Rev.1.6 Figure 1-2: SOT-23/SOT-89 Application Circuit www.yobon.com.tw 1 YB1231 HV600mA, Low-Noise LDO Regulator Pin Configuration Figure 2: Pin Configuration Pin Description Table 1 Name Description VIN Unregulated input supply. Bypass with a capacitor to GND. GND Ground pin. EN VOUT YB1231 Rev.1.6 Pull high to enable the regulator. Regulated output voltage. Bypass with a capacitor to GND. www.yobon.com.tw 2 YB1231 HV600mA, Low-Noise LDO Regulator Ordering Information Marking Information Absolute Maximum Ratings (Note 1) Supply Voltage............................ -0.3V to 6V Output Voltage ................ -0.3V to (VIN+0.3V) Output Short-Circuit Duration..............Infinite Junction Temperature Range............ +150℃ Storage Temperature Range...... -65℃ to +150℃ Lead Temperature............................. +250℃ Recommended Operating Conditions (Note 2) Input Supply Voltage............... 2.0V to 5.5V Operating Temperature........-40℃ to +85℃ Thermal In formation (Note 3) Thermal Resistance (SOT-23/25, θJA) ... 280℃/W Thermal Resistance (SOT-89, θJA)......... 180℃/W Internal Power Dissipation (SOT-23/25, PD) . 0.4W Internal Power Dissipation (SOT-89, PD)..... 0.55W Note: 1. Exceeding these ratings may damage the device. 2. The device is not guaranteed to function outside of its operating conditions. 3. θJA is measured in free air at TA = 25℃ on a low effective thermal conductivity board. YB1231 Rev.1.6 www.yobon.com.tw 3 YB1231 HV600mA, Low-Noise LDO Regulator Electrical Characteristics Table 2 VIN = ( VOUT + 1V ), CIN = COUT = 2.2μF, VEN = VIN, TA=25°C, unless otherwise noted. Description Input Voltage Range Output Voltage Output Voltage Accuracy Output Current Limit Dropout Voltage (Note 1) Symbol Test Conditions VIN MIN TYP MAX Units 2.0 5.5 V VOUT Predefined 3.2 4.5 V ΔVOUT IOUT = 10mA -2.0 +2.0 % ISC VDROP Short-Circuit Output 420 VOUT = 4.5V, IOUT = 600mA 440 VOUT = 4.0V, IOUT = 600mA 470 VOUT = 3.6V, IOUT = 600mA 500 VOUT = 3.3V, IOUT = 600mA 530 VOUT = 3.2V, IOUT = 600mA 550 Iground = IIN - IOUT 100 mA mV 160 μA Ground Current IG Line Regulation ΔVLINE VIN=(VOUT+1V) to 5.5V, IOUT=10mA 0.4 %/V Load Regulation ΔVLOAD IOUT = 1mA to 600mA 1.7 % Shutdown Supply Current Ripple Rejection (PSRR) ISD PSRR Shutdown Exit Delay (Note 2) 1 EN = 0V f = 100Hz, IOUT = 10mA 51 f = 1KHz, IOUT = 10mA 51 f = 10KHz, IOUT = 10mA 45 VOUT = 3.3V, Rload = 11 ohm 36 μA dB 100 μs 0.4 V VIN V EN Logic Low Level VIL VIN = 2.0V to 5.5V EN Logic High Level VIH VIN = 2.0V to 5.5V EN Input Bias Current IBEN VIN = EN = VOUT +1V 0.01 μA Thermal Shutdown TSD Shutdown Temperature 160 °C Thermal Hysteresis THYS VOUT = 3.3V, IOUT = 100mA 20 °C 1.5 Note : 1. The drop out voltage varies depending on output voltage selection. Dropout is defined as VIN – VOUT when VOUT is 100mV below nominal VOUT where VIN = VOUT + 1V for nominal VOUT. 2. Time needed for VOUT to reach 90% of final value. YB1231 Rev.1.6 www.yobon.com.tw 4 YB1231 HV600mA, Low-Noise LDO Regulator Typical Performance Characteristics VIN = ( VOUT + 1V ), CIN = COUT = 2.2μF, VEN = VIN, TA=25°C, unless otherwise noted. Dropout Voltage vs. Output Voltage Ground Current vs. Input Voltage Load Transient Response (1) YB1231 Rev.1.6 Dropout Voltage vs. Load Current Dropout Voltage vs. Temperature Load Transient Response (2) www.yobon.com.tw 5 YB1231 HV600mA, Low-Noise LDO Regulator Shutdown Exit Delay Shutdown Delay Output Voltage vs. Temperature Line Transient Response (10mA) YB1231 Rev.1.6 www.yobon.com.tw Output Noise Measurement PSRR vs. Frequency 6 YB1231 HV600mA, Low-Noise LDO Regulator Function Block IN EN SHUTDOWN AND POWER-ON CONTROL ERROR AMP MOS DRIVER WITH LIMIT P OUT THERMAL SENSOR REFERENCE AND NOISE BYPASS GND Figure 3: Function Block Functional Description The YB1231 is an ultra-low-noise, low-quiescent current, low-dropout linear regulator. It is supplied in a SOT-23 / SOT-25 / SOT-89 package for different applications. These devices can supply loads up to 600mA. As shown in the Functional Block Diagram, the YB1231 consists of a reference and noise bypass circuit, error amplifier, output drive transistor, internal feedback voltage divider, thermal sensor, and short circuit current limiter. The internal reference is connected to the error amplifier’s inverting input. The error amplifier compares this reference with the feedback voltage and amplifies the difference. If the feedback voltage is lower than the reference voltage, the pass-transistor gate is pulled low. This YB1231 Rev.1.6 allows more current to pass to the output and increases the output voltage. If the feedback voltage is too high, the pass transistor gate is pulled high, allowing less current to pass to the output. The parts are available with preset output voltages ranging from 3.2V to 4.5V. Stability The YB1231 is a high performance LDO emphasizing stability with low output capacitance. It is able to maintain stability with an output capacitor as low as 2.2μF. The output capacitor can also be increased to optimize performance. The YB1231 will remain stable and in regulation with no load, unlike many other voltage regulators. Internal P-Channel Pass Transistor The YB1231 features a low impedance www.yobon.com.tw 7 YB1231 HV600mA, Low-Noise LDO Regulator P-channel MOSFET pass transistor. This provides several advantages over similar designs using a PNP pass transistor, including low operating power and longer battery life. The YB1231 consumes only 100µA of quiescent current under most conditions. Output Short-Circuit Current Limit The YB1231 includes a current limiter, which monitors and controls the pass transistor’s gate voltage, limiting the output current to about 420mA, for example, in a short-circuit output situation. Shutdown The YB1231 also features a low-power active shutdown mode. It has a switch that turns off the device when disabled. This allows the output capacitor and load to discharge and de-energize the load. In the shutdown mode, the internal functional blocks, such as voltage reference and the error amplifier, are turned off completely, and the quiescent current is less than 1µA. Thermal Protection Shutdown The thermal protection shutdown function protects the device from operating in over temperature condition. When the junction temperature exceeds +160°C, the thermal sensor signals the shutdown logic, turning off the pass transistor and allowing the IC to cool down. The thermal sensor turns the pass transistor on again after the IC’s junction temperature drops to +140°C. up, the output capacitor and output load are charged with a reduced output current. Shortly after the initial power up, the soft-start feature is terminated and normal operation is resumed. Application Information Enable/Shutdown The YB1231 comes with an active-high enable pin that allows the regulator to be enabled. Forcing the enable pin low disables the regulator and puts it into the shutdown mode. This pin cannot be left floating as it may cause an undetermined state. Input/Output Capacitor It is recommended to use a 2.2µF capacitor on the YB1231 input and a 2.2µF capacitor on the output. For high regulation performance, larger input capacitor values and lower ESRs provide better noise rejection and line-transient response. The output noise, load-transient response, stability, and power-supply rejection can be improved by using large output capacitors. Low ESR ceramic capacitors provide optimal performance and save space. Soft-Start Circuitry The YB1231 includes a soft-start circuitry to limit inrush current at turn-on. During power YB1231 Rev.1.6 www.yobon.com.tw 8 YB1231 HV600mA, Low-Noise LDO Regulator Package Information (SOT-23) E1 E YB1231 Rev.1.6 www.yobon.com.tw 9 YB1231 HV600mA, Low-Noise LDO Regulator Package Information (SOT-25) D e1 e YB1231 Rev.1.6 www.yobon.com.tw 10 YB1231 HV600mA, Low-Noise LDO Regulator Package Information (SOT-89) L A C NOTICE: y The information described herein is subject to change without notice. y Yobon does not assume any responsibility for use of any circuitry or applications described herein, nor does it convey any patent license. YB1231 Rev.1.6 www.yobon.com.tw 11