LM2825N-3.3

LM2825 NSC | Alldatasheet

Document overview

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Technical content

Features

n Minimum design time required n 3.3V, 5V and 12V fixed output versions n Two adjustable versions allow 1.23V to 15V outputs n Wide input voltage range, up to 40V n Low-power standby mode, IQ typically 65 µA n High efficiency, typically 80% n ±4% output voltage tolerance n Excellent line and load regulation n TTL shutdown capability/programmable Soft-start n Thermal shutdown and current limit protection n −40˚C to +85˚C ambient temperature range

Applications

n Simple high-efficiency step-down (buck) regulator n On-card switching regulators n Efficient pre-regulator for linear regulators n Distributed power systems n DC/DC module replacement Standard Application (Fixed output voltage versions) Radiated EMI Radiated emission of electromagnetic fields is measured at 10m distance. The emission levels are within the Class B limits stipulated by CISPR 22. 30. . . .230 MHz 30 dB µV/m 230. . . .1000 MHz 37 dB µV/m 1. . . .10 GHz 46 dB µV/m Connection Diagram

Ordering Information

Order Number LM2825N-3.3, LM2825N-5.0, LM2825N-12, LM2825N-ADJ or LM2825HN-ADJ See NS Package Number NA24F DS012661-27 DS012661-1 DS012661-2 “NC (Do not use)” pins: SeeFigure 11. Top View May 1997 LM2825 Integrated Power Supply 1A DC-DC Converter © 1997 National Semiconductor Corporation DS012661 www.national.com

Absolute Maximum Ratings (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Maximum Input Supply (V IN) +45V SD/SS Pin Input Voltage (Note 2) 6V Output Pin Voltage (3.3V, 5.0V and ADJ) −1V ≤ V ≤ 9V (12V and H-ADJ) −1V ≤ V ≤ 16V ADJ Pin Voltage (ADJ, H-ADJ only) −0.3V ≤ V ≤ 25V Power Dissipation Internally Limited Storage Temperature Range −40˚C to +125˚C ESD Susceptibility Human Body Model (Note 3) 2 kV Lead Temperature (Soldering 10 sec.) 260˚C Operating Ratings Ambient Temperature Range −40˚C ≤ TA ≤ +85˚C Junction Temperature Range −40˚C ≤ TJ ≤ +125˚C Input Supply Voltage (3.3V version) 4.75V to 40V Input Supply Voltage (5V version) 7V to 40V Input Supply Voltage (12V version) 15V to 40V Input Supply Voltage (-ADJ, H-ADJ) 4.5V to 40V LM2825-3.3 Electrical Characteristics(Note 4) Specifications with standard type face are for TA = 25˚C, and those withboldface typeapply overfull Operating Tempera- ture Range. Test CircuitFigure 2. Symbol Parameter Conditions LM2825-3.3 Units (Limits)Typical Limit (Note 6) (Note 7) VOUT Output Voltage 4.75V ≤ VIN ≤ 40V, 0.1A≤ ILOAD ≤ 1A 3.3 V 3.168/3.135 V(min) 3.432/3.465 V(max) Line Regulation 4.75V ≤ VIN ≤ 40V 1.5 mV ILOAD = 100 mA Load Regulation 0.1A ≤ ILOAD ≤ 1A 8 mV VIN = 12V Output Ripple Voltage V IN = 12V, ILOAD = 1A 40 mV p-p η Efficiency V IN = 12V, ILOAD = 0.5A 75 % LM2825-5.0 Electrical Characteristics(Note 4) Specifications with standard type face are for TA = 25˚C, and those withboldface typeapply overfull Operating Tempera- ture Range. Test CircuitFigure 2. Symbol Parameter Conditions LM2825-5.0 Units (Limits)Typical Limit (Note 6) (Note 7) VOUT Output Voltage 7V ≤ VIN ≤ 40V, 0.1A≤ ILOAD ≤ 1A 5.0 V 4.800/4.750 V(min) 5.200/5.250 V(max) Line Regulation 7V ≤ VIN ≤ 40V 2.7 mV ILOAD = 100 mA Load Regulation 0.1A ≤ ILOAD ≤ 1A 8 mV VIN = 12V Output Ripple Voltage V IN = 12V, ILOAD = 1A 40 mV p-p η Efficiency V IN = 12V, ILOAD = 0.5A 80 % www.national.com 2

Specifications with standard type face are for TA = 25˚C, and those withboldface typeapply overfull Operating Tempera- ture Range. Test CircuitFigure 2. Symbol Parameter Conditions LM2825-12 Units (Limits)Typical Limit (Note 6) (Note 7) VOUT Output Voltage 15V ≤ VIN ≤ 40V, 0.1A≤ ILOAD ≤ 0.75A 12.0 V 11.52/11.40 V(min) 12.48/12.60 V(max) Line Regulation 15V ≤ VIN ≤ 40V 8.5 mV ILOAD = 100 mA Load Regulation 0.1A ≤ ILOAD ≤ 0.75A 12 mV VIN = 24V Output Ripple Voltage VIN = 24V, ILOAD = 1A 100 mV p-p η Efficiency V IN = 24V, ILOAD = 0.5A 87 % Specifications with standard type face are for TA = 25˚C, and those withboldface typeapply overfull Operating Tempera- ture Range. Test CircuitFigure 3. Symbol Parameter Conditions LM2825-ADJ Units (Limits)Typical Limit (Note 6) (Note 7) VADJ Adjust Pin Voltage 4.5V ≤ VIN ≤ 40V, 0.1A≤ ILOAD ≤ 1A 1.230 V 1.23V ≤ VOUT ≤ 8V 1.193/ 1.180 V(min) 1.267/1.280 V(max) η Efficiency V IN = 12V, ILOAD = 0.5A 74 % VOUT Programmed for 3V. See Circuit ofFigure 3 Specifications with standard type face are for TA = 25˚C, and those withboldface typeapply overfull Operating Temperature Range . Test CircuitFigure 3. Symbol Parameter Conditions LM2825H-ADJ Units (Limits)Typical Limit (Note 6) (Note 7) VADJ Adjust Pin Voltage 9V ≤ VIN ≤ 40V, 0.1A≤ ILOAD ≤ 0.55A 1.230 V 7V ≤ VOUT ≤ 15V 1.193/ 1.180 V(min) 1.267/1.280 V(max) η Efficiency V IN = 24V, ILOAD = 0.5A 87 % VOUT Programmed for 12V. See Circuit ofFigure 3 3 www.national.com

All Output Voltage Versions Electrical Characteristics Specifications with standard type face are for TA = 25˚C, and those withboldface typeapply overfull Operating Range.Un- less otherwise specified, VIN = 12V for 3.3V, 5.0V and ADJ versions, VIN = 24V for 12V and H-ADJ versions, ILOAD = 100 mA. Symbol Parameter Conditions LM2825-XX Units (Limits)Typical Limit (Note 6) (Note 7) ICL DC Output Current Limit R L = 0Ω 1.4 A

1.2 A(min)

2.4 A(max)

SD/SS Pin = 3.1V 5 mA (Note 8) 10 mA(max) ISTBY Standby Quiescent Current SD/SS Pin = 0V 65 µA (Note 8) 200 µA(max) IADJ Adjust Pin Bias Current Adjustable Versions Only, VFB = 1.3V 6 nA 50/100 nA(max) fO Oscillator Frequency (Note 9) 150 kHz θJA Thermal Resistance Junction to Ambient (Note 10) 30 ˚C/W SHUTDOWN/SOFT-START CONTROL Test CircuitFigure 2 VSD Shutdown Threshold Voltage 1.3 V Low (Shutdown Mode) 0.6 V(max) High (Soft-start Mode) 2.0 V(min) VSS Soft-start Voltage V OUT = 20% of Nominal Output Voltage 2 V VOUT = 100% of Nominal Output Voltage 3 ISD Shutdown Current V SHUTDOWN = 0.5V 5µ A (Note 8) 10 µA(max) ISS Soft-start Current V SOFT-START = 2.5V 1.6 µA (Note 8) 5 µA(max) Note 1:Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is in- tended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2:Voltage internally clamped. If clamp voltage is exceeded, limit current to a maximum of 5 mA. Note 3:The human body model is a 100 pF capacitor discharged through a 1.5k resistor into each pin. Note 4:When the LM2825 is used as shown inFigure 2test circuit, system performance will be as shown in Electrical Characteristics. Note 5:When the LM2825 is used as shown inFigure 3test circuit, system performance will be as shown in Electrical Characteristics. Note 6:Typical numbers are at 25˚C and represent the most likely norm. Note 7:All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face) when output current is limited to the value given in the temperature derating curves. See the application section for curves. All limits at temperature extremes are guaranteed using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL). Note 8:I LOAD = 0A. Note 9:The switching frequency is reduced when the second stage current limit is activated. The amount of reduction is determined by the severity of current over- load. Note 10:Junction to ambient thermal resistance (no external heat sink) for the DIP-24 package with the leads soldered to a printed circuit board with (1 oz.) copper area of approximately 2 in2. www.national.com 4

Typical Performance Characteristics(Circuits ofFigure 2and Figure 3) Unless otherwise specified, VIN = 12V for 3.3V, 5.0V and ADJ versions, VIN = 24V for 12V and H-ADJ versions, ILOAD = 100 mA, TA = 25˚C Normalized Output Voltage DS012661-3 Efficiency DS012661-4 Dropout Voltage DS012661-5 Line Regulation DS012661-6 Load Regulation DS012661-7 Output Ripple Voltage DS012661-8 Operating Quiescent Current DS012661-9 Shutdown Quiescent Current DS012661-10 Switching Frequency DS012661-11 5 www.national.com

FIGURE 1. Typical Load Transient Response

Physical Dimensionsinches (millimeters) unless otherwise noted LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DE- VICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMI- CONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or sys- tems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose fail- ure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. A critical component in any component of a life support device or system whose failure to perform can be rea- sonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com www.national.com National Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 1 80-530 85 85 English Tel: +49 (0) 1 80-532 78 32 Français Tel: +49 (0) 1 80-532 93 58 Italiano Tel: +49 (0) 1 80-534 16 80 National Semiconductor Hong Kong Ltd. 13th Floor, Straight Block, Ocean Centre, 5 Canton Rd. Tsimshatsui, Kowloon Hong Kong Tel: (852) 2737-1600 Fax: (852) 2736-9960 National Semiconductor Japan Ltd. Tel: 81-3-5620-6175 Fax: 81-3-5620-6179 24-Lead (0.600" Wide) Molded Dual-In-Line Package Order Number LM2825N-3.3, LM2825N-5.0, LM2825N12, LM2825N-ADJ or LM2825HN-ADJ LM2825 Integrated Power Supply 1A DC-DC Converter National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.