芯美电子 EUP7961 1A Ultra Low-Dropout Linear Regulator DESCRIPTION FEATURES The EUP7961 is a 1A low-dropout linear regulator that provides a low voltage, high current output with a minimum of external components. It offers high precision, ultra-low dropout, and low ground current. The EUP7961 operates from an input of 2.5V to 5.5V. This regulator uses small, 1µF ceramic input capacitors and 4.7µF ceramic output capacitors to deliver 1A output current. High bandwidth provides excellent transient response. It is designed to drive digital circuits requiring low voltage at high currents (i.e., PLDs, DSPs, microcontrollers, etc.). Other features include thermal and current limit protection, a logic-control shutdown mode and an error flag output that goes low when the output voltage drops 10% below nominal value. It is available in fixed output voltages of 1.5V, 1.8V, 2.5V, 3.3V and as an adjustable device with a 0.8V reference voltage. The adjustable output voltage can be set from 0.8V to 4.5V. z z z z z z z z z z 1A Guaranteed Output Current 300mV Dropout Voltage at 1A Output Stable with Ceramic Capacitors ±1.8% Output Voltage Accuracy 300µA Low-Ground Pin Current 0.1µA Quiescent Current in Shutdown Mode Excellent Line and Load Regulation Thermal Shutdown and Current Limit Protection Error Flag Indication Available in SOT223, SOP-8 and SOT-89 Packages RoHS Compliant and 100% Lead (Pb)-Free APPLICATIONS z z z z LDO Linear Regulator for Low-Voltage Digital IC PC Add-In Cards High Efficiency Linear Power Supplies Post Regulator Typical Application Circuit Figure1. DS7961 Ver 1.2 Dec. 2006 1 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Block Diagram Figure2. Pin Configurations Package Type Package Type Pin Configurations SOT223-3 SOT223-3 (B) SOT-89 SOP-8 Pin Configurations Pin Description PIN SOT-223 VEN - SOT-223 (B) - VIN 1 GND VOUT ERROR SOT-89 SOP-8 - 1 Enable Input. Logic high=enable, Logic low=shutdown 3 3 2 Input Voltage of the LDO 2 1 2 5,6,7,8 3 2 1 3 - 4 - ADJ DS7961 Ver 1.2 Dec. 2006 - DESCRIPTION Ground: TAB is connected to ground Output voltage of the LDO ERROR Flag Output. Active-low indicated an output fault condition Adjustable Regulator Feedback Input. Connect to resistor voltage divider 2 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Ordering Information Order Number Package Type EUP7961-15BIR1 SOT223 EUP7961-18BIR1 SOT223 EUP7961-25BIR1 SOT223 EUP7961-33BIR1 SOT223 EUP7961B-15BIR1 SOT223 EUP7961B-18BIR1 SOT223 EUP7961B-25BIR1 SOT223 EUP7961B-33BIR1 SOT223 EUP7961-15CIR1 SOT-89 EUP7961-18CIR1 SOT-89 EUP7961-25CIR1 SOT-89 EUP7961-33CIR1 SOT-89 EUP7961-15DIR1 SOP-8 EUP7961-18DIR1 SOP-8 EUP7961-25DIR1 SOP-8 EUP7961-33DIR1 SOP-8 EUP7961DIR1 SOP-8 Marking Operating Temperature range xxxx P7961C xxxx P7961D xxxx P7961B xxxx P7961H xxxx 7961CB xxxx 7961DB xxxx 7961BB xxxx 7961HB xxxx P7961C xxxx P7961D xxxx P7961B xxxx P7961H xxxx EUP7961 C xxxx EUP7961 D xxxx EUP7961 B xxxx EUP7961 H xxxx EUP7961 A -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C -40 °C to 125°C EUP7961- □ □ □ □ □ □ Lead Free Code 1: Lead Free 0: Lead Packing R: Tape & Reel Operating temperature range I: Industry Standard Package Type: B: SOT223 C: SOT89 Output Voltage DS7961 Ver 1.2 Dec. 2006 D: SOP 3 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Absolute Maximum Ratings Supply Voltage VIN ---------------------------------------------------------------------- 5.5V Package Thermal Resistance SOT-223, θJA ---------------------------------------------------------------------- 115°C /W SOP-8, θJA ------------------------------------------------------------------------- 125°C /W Power Dissipation, PD@TA=25°C SOT-223 ------------------------------------------------------------------------------ 0.87W SOP-8 --------------------------------------------------------------------------------- 0.8W Junction Temperature ------------------------------------------------------------------- 150°C Storage Temperature ------------------------------------------------------ -65°C to +150°C Lead Temp -----------------------------------------------------------------------------260°C ESD Rating Human Body Model ---------------------------------------------------------------------- 2kV Operating Ratings Supply Voltage VIN ---------------------------------------------------------------- 2.5 to 5.5V Enable Input Voltage -------------------------------------------------------------- 0V to 5.5V Junction Temperature ------------------------------------------------------ -40°C to +125°C Electrical Characteristics Limits in standard typeface are for TJ =25°C. Unless otherwise specified: VIN= VOUT(nom) +1V, IL=10mA,COUT=4.7µF Symbol ΔVOUT Parameter Conditions Output Voltage Tolerance VOUT+1V ≤ VIN ≤ 5.5V 10mA ≤ IL ≤ 1A Line Regulation VOUT+1V ≤ VIN ≤ 5.5V Load Regulation 10mA ≤ IL ≤ 1A VIN -VOUT Dropout Voltage IGND IO(PK) Ground Pin Current in Normal Operation Mode EUP7961 Typ Max. % 0.1 0.24 % 0.08 0.32 % IL = 100mA 35 50 IL = 1A 300 500 IL = 10mA 300 IL = 1A 500 VEN ≤ 0.3V Peak Output Current VO ≥ VO(NOM) -4% -1.8 Unit 1.8 Ground Pin Current in Shutdown Mode 0.01 Short Circuit Protection ISC Short Circuit Current DS7961 Ver 1.2 Dec. 2006 Min mV µA 10 µA 1.5 A 1.7 A 4 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Electrical Characteristics Limits in standard typeface are for TJ =25°C. Unless otherwise specified: VIN= VOUT(nom) +1V, IL=10mA,COUT=4.7µF Symbol VIH Parameter Conditions Output = High Enable Threshold VIL EUP7961 Min Typ Max. 1.4 VIN Output = Low 0 TdOFF Turn-off delay IL = 1A 20 TdON Turn-on delay IL = 1A 20 VEN Pin Input Current VEN=VIN 0.1 IEN ERROR VT Flag Threshold VTH VEF(Sat) Td IIK Imax Threshold Hysteresis ERROR Flag Pin Leakage ERROR Flag Pin Sink en Ripple Rejection Output Noise Voltage VError=0.5V VIN=VOUT+1V COUT=10uF VOUT=3.3V, f=120Hz BW=10Hz -100kHz VOUT=2.5V V µs 1 µA 10 % 5 % 0.02 Current Current AC Parameters PSRR ISINK=100µA Flag Saturation Flag Reset Delay ERROR 0.3 Unit 0.1 V 1 µs 1 nA 3.8 mA 60 dB 150 µV(rms) 150 °C 10 °C Over Temperature Protection TSH(t) TSH(h) Shutdown Threshold Thermal Shutdown Hysteresis DS7961 Ver 1.2 Dec. 2006 5 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Typical Operating Characteristics DS7961 Ver 1.2 Dec. 2006 6 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 DS7961 Ver 1.2 Dec. 2006 EUP7961 7 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Application Note External Capacitors Like any low-dropout regulator, the EUP7961 requires external capacitors for regulator stability. These capacitors must be correctly selected for good performance. Input Capacitor An input capacitance of 1µF is required between the EUP7961 input pin and ground (the amount of the capacitance may be increased without limit). This capacitor must be located a distance of not more than 1cm from the input pin and returned to a clean analog ground. Any good quality ceramic, tantalum, or film capacitor may be used at the input. If a tantalum capacitor is used at the input, it must be guaranteed by the manufacturer to have a surge current rating sufficient for the application. There are no requirements for the ESR on the input capacitor, but tolerance and temperature coefficient must be considered when selecting the capacitor to ensure the capacitance will be 1µF over the entire operating temperature range. Output Capacitor The EUP7961 is designed specifically to work with very small ceramic output capacitors. A ceramic capacitor (temperature characteristics X7R, X5R, Z5U, or Y5V) in 4.7 to 22µF range with 5mΩ to 200mΩ ESR range is suitable in the EUP7961 application circuit. The output capacitor must meet the requirement for minimum amount of capacitance and also have an ESR (Equivalent Series Resistance) value which is within a stable range (5mΩ to 200mΩ) No-Load Stability The EUP7961 will remain stable and in regulation with no external load. This is specially important in CMOS RAM keep-alive applications. ERROR Flag Operation The EUP7961 produces a logic low signal at the ERROR Flag pin when the output drops out of regulation due to low input voltage, current limiting, or thermal limiting. This flag has a built in hysteresis. The internal ERROR flag comparator has an open drain output stage. Hence, the ERROR pin should be pulled high through a pull up resistor. The ERROR pin must be connected to ground if this function is not used. It should also be noted that when the shutdown pin is pulled low, the ERROR pin is forced to be invalid for reasons of saving power in shutdown mode. Adjustable Operation The adjustable version of the EUP7961 has an output voltage range of 0.8V to 4.5V. The output voltage of the EUP7961 adjustable regulator is programmed using an external resistor divider as shown in Figure3. The output voltage is calculated using: V =V O ref × (1 + R1 R ) 2 Where: Vref= 0.8V typ. (the internal reference voltage) Utilize the following equation for adjusting the output to a particular voltage: V PI = R O − 1 2 0.8V Choose R2=50k to optimize accuracy, power supply rejection, noise and power consumption. On/Off Input Operation The EUP7961 is turned off by pulling the VEN pin low, and turned on by pulling it high. If this feature is not used, the VEN pin should be tied to VIN to keep the regulator output on at all time. To assure proper operation, the signal source used to drive the VEN input must be able to swing above and below the specified turn-on/off voltage thresholds listed in the Electrical Characteristics section under VIL and VIH. DS7961 Ver 1.2 Dec. 2006 8 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Power Dissipation EUP7961 can deliver a continuous current of 2A over the full operating temperature range. A heatsink may be required depending on the maximum power dissipation and maximum ambient temperature of the application. Under all possible conditions, the junction temperature must be within the range specified under operating conditions. The total power dissipation of the device is given by: ( ) ( ) P = V −V I + V I D IN IN GND OUT OUT Where IGND is the operating ground current of the device (specified under Electrical Characteristics). The maximum allowable temperature rise (TRmax) depends on the maximum ambient temperature (TAmax) of the application, and the maximum allowable junction temperature (TJmax): TRmax= TJmax-TAmax The maximum allowable value for junction to ambient Thermal Resistance, θJA , can be calculated using the formula: PCB Layout Good PC layout practices must be used or instability can be induced because of ground loops and voltages drops. The input and output capacitors must be directly connected to the input, output, and ground pins of the regulator using traces which do not have other currents flowing in them. The best way to do this is to lay out CIN and COUT near the device with short traces to the VIN, VOUT, and ground pins. The regulator ground pin should be connected to the external circuit ground so that the regulator and its capacitors have a “single point ground”. It should be noted that stability problems have been seen in applications where “vias” to an internal ground plane were used at the ground points of the IC and the input and output capacitors. This was caused by varying ground potentials at these nodes resulting from current flowing through the ground plane. Using a single point ground technique for the regulator and it’s capacitors fixed the problem. Since high current flows through the traces going into VIN and coming from VOUT, Kelvin connect the capacitor leads to these pins so there is no voltage drop in series with the input and output capacitors. θJA =TRmax/PD DS7961 Ver 1.2 Dec. 2006 9 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 Packaging Information SOT223-3 SYMBOLS A A1 B B1 D E e H L DS7961 Ver 1.2 Dec. 2006 MILLIMETERS MIN. MAX. 1.50 1.80 0.00 0.10 0.60 0.80 2.90 3.10 6.50 3.50 2.30 6.70 7.30 0.80 1.10 INCHES MIN. 0.059 0.000 0.024 0.114 MAX. 0.071 0.004 0.031 0.122 0.256 0.138 0.090 0.264 0.031 0.287 0.043 10 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 SOP-8 SYMBOLS A A1 D E1 E L b e DS7961 Ver 1.2 Dec. 2006 MILLIMETERS MIN. MAX. 1.35 1.75 0.05 0.25 4.90 3.90 5.80 6.20 0.40 1.27 0.33 0.51 1.27 INCHES MIN. 0.053 0.002 0.193 0.153 0.228 0.016 0.013 0.500 MAX. 0.069 0.010 0.244 0.050 0.020 11 联系电话：１５９９９６４４５７９ ８３１５１７１５ 芯美电子 EUP7961 SOT-89 SYMBOLS A L B1 B C D D1 H E e DS7961 Ver 1.2 Dec. 2006 MILLIMETERS MIN. MAX. 1.40 1.60 0.89 1.20 0.36 0.48 0.44 0.56 0.35 0.44 4.40 4.60 1.35 1.83 3.94 4.25 2.29 2.60 1.50 INCHES MIN. 0.055 0.035 0.014 0.017 0.014 0.173 0.053 0.155 0.090 0.059 MAX. 0.063 0.047 0.019 0.022 0.017 0.181 0.072 0.167 0.102 12 联系电话：１５９９９６４４５７９ ８３１５１７１５