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Details, datasheet, quote on part number:LM2621EVAL
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| Part: | LM2621EVAL |
| Category: | Power Management => Regulators => Switching Regulators |
| Description: | LM2621 - Low Input Voltage, Step-up DC-DC, Package: Evaluation Board, Pin Nb=- |
| Company: | National Semiconductor Corporation |
| Datasheet: | Download LM2621EVAL datasheet File size : 261 kB |
| Request For quote: | Find where to buy LM2621EVAL
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Datasheet text preview:
LM2621 Low Input Voltage, Step-Up DC-DC Converter
February 2000
LM2621 Low Input Voltage, Step-Up DC-DC Converter
General Description
The LM2621 is a high efficiency, step-up DC-DC switching regulator for battery-powered and low input voltage systems. It accepts an input voltage between 1.2V and 14V and converts it into a regulated output voltage. The output voltage can be adjusted between 1.24V and 14V. It has an internal 0.17 N-Channel MOSFET power switch. Efficiencies up to 90% are achievable using the LM2621. The high switching frequency (adjustable up to 2MHz) of the LM2621 allows for tiny surface mount inductors and capacitors. Because of the unique constant-duty-cycle gated oscillator topology very high efficiencies are realized over a wide load range. The supply current is reduced to 80µA because of the BiCMOS process technology. In the shutdown mode, the supply current is less than 2.5µA. The LM2621 is available in a Mini-SO-8 package. This package uses half the board area of a standard 8-pin SO and has a height of just 1.09 mm.
Features
n Small Mini-SO8 Package (Half the Footprint of Standard 8-Pin SO Package) n 1.09 mm Package Height n Up to 2 MHz Switching Frequency n 1.2V to 14V Input Voltage n 1.24V - 14V Adjustable Output Voltage n Up to 1A Load Current n 0.17 Internal MOSFET n Up to 90% Regulator Efficiency n 80 µA Typical Operating Current n < 2.5µA Guaranteed Supply Current In Shutdown
Applications
n n n n n n n n n n PDAs, Cellular Phones 2-Cell and 3-Cell Battery-Operated Equipment PCMCIA Cards, Memory Cards Flash Memory Programming TFT/LCD Applications 3.3V to 5.0V Conversion GPS Devices Two-Way Pagers Palmtop Computers Hand-Held Instruments
Typical Application Circuit
DS100934-12
© 2000 National Semiconductor Corporation
DS100934
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LM2621
Connection Diagram
Mini SO-8 (MM) Package
DS100934-18
Top View
Ordering Information
Order Number LM2621MMX LM2621MM Package Type Mini SO-8 Mini SO-8 NSC Package Drawing MUA08A MUA08A Package Marking S06A S06A Supplied As 3000 Units on Tape and Reel 1000 Units on Tape and Reel
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LM2621
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. SW Pin Voltage BOOT, VDD, EN and FB Pins FREQ Pin JA (Note 2) TJmax (Note 2) Storage Temperature Range Lead Temp. (Soldering, 5 sec) -0.5 V to 14.5V -0.5V to 10V 100µA 240°C/W 150°C -65°C to +150°C 260°C
Power Dissipation (TA=25°C) (Note 2) ESD Rating (Note 3)
500mW 2kV
Operating Conditions (Note 1)
VDD Pin FB, EN Pins BOOT Pin Ambient Temperature (TA) 2.5V to 5V 0 to VDD 0 to 10V -40°C to +85°C
Electrical Characteristics
Limits in standard typeface are for TJ = 25°C, and limits in boldface type apply over the full operating temperature range of -40°C to +85°C. Unless otherwise specified: VDD = VOUT = 3.3V. Symbol VIN_ST VIN_OP VFB VOUT_MAX VHYST Parameter Minimum Start-Up Supply Voltage (Note 4) Minimum Operating Supply Voltage (once started) FB Pin Voltage Maximum Output Voltage Hysteresis Voltage (Note 7) Efficiency VIN = 3.6V; VOUT = 5V; ILOAD = 500mA VIN = 2.5V; VOUT = 3.3V; ILOAD = 200mA D IDD ISD ICL RDS_ON Switch Duty Cycle Operating Quiescent Current (Note 6) Shutdown Quiescent Current (Note 7) Switch Peak Current Limit MOSFET Switch On Resistance EN Pin Voltage Low (Note 8) EN Pin Voltage High (Note 8) 0.7VDD FB Pin > 1.3V; EN Pin at VDD VDD, BOOT and SW Pins at 5.0V; EN Pin < 200mV Condition ILOAD = 0mA ILOAD = 0mA Typ 1.1 0.65 1.24 14 30 87 87 70 80 0.01 2.85 0.17 60 80 110 2.5 % 45 1.2028 1.2772 Min Max 1.2 Units V V V V mV
% µA µA A
Enable Section VEN_LO VEN_HI 0.15VDD V V
Note 1: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Electrical specifications do not apply when operating the device outside of its rated operating conditions. Note 2: The maximum power dissipation must be derated at elevated temperatures and is dictated by Tjmax (maximum junction temperature), JA (junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any temperature is Pdmax = (Tjmax - TA)/ JA or the number given in the Absolute Maximum Ratings, whichever is lower. Note 3: The human body model is a 100 pF capacitor discharged through a 1.5 k resistor into each pin. For Pin 8 (SW) the ESD rating is 1.5 kV. Note 4: Output in regulation, VOUT = VOUT (NOMINAL) ± 5% Note 5: This is the hysteresis value of the internal comparator used for the gated-oscillator control scheme. Note 6: This is the current into the VDD pin. Note 7: This is the total current into pins VDD, BOOT, SW and FREQ. Note 8: When the EN pin is below VEN_LO, the regulator is shut down; when it is above VEN_HI, the regulator is operating.
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