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Details, datasheet, quote on part number:LM3590
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Datasheet text preview:
LM3590 Series White LED Driver
November 2003
LM3590 Series White LED Driver
General Description
The LM3590 is a White LED constant current driver capable of supplying up to 3 White LEDs connected in series with 20mA. This device operates over a wide 6V-12.6V input voltage range. The output can accomodate LEDs with a combined forward voltage of up to 11.5V, from a 12V input supply. The LED drive current is programmed by using an external resistor on the ISET pin. LED brightness can be linearly varied up to the programmed LED current by applying a Pulse Width Modulated (PWM) signal to the EN pin of the device. The LED output current of the LM3590 is tightly controlled over temperature and voltage. LED Current matching is guaranteed due to the series configuration of the LEDs. The series topology also simplifies the connection between the White LEDs in the display module and the LM3590 since only one connection is required. The LM3590 typically draws only 50µA when operating in the no-load condition and draws less than 0.1µA when the device is shut down. The LM3590 is available in a small 5-pin SOT23 package.
Features
n n n n n n n n n n Drives up to 3 stacked white LEDs 6.0V-12.6V input voltage range Up to 20mA LED output current Excellent LED current matching guaranteed by series configuration Single connection to the White LEDs in the display module Tightly controlled programmable current source Low shutdown current (0.1µA typ.) PWM brightness control Very small solution size SOT23-5 package: 3mm x 3mm x 1.0mm (LxWxH)
Applications
n White LED Display Backlights n Keypad Backlights n General purpose constant current driver for high forward-voltage LEDs
Typical Application Circuit
20081301
20081305
© 2003 National Semiconductor Corporation
DS200813
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LM3590
Connection Diagram
20081302
Ordering Information
Order Number LM3590MF LM3590MFX Package Description SOT23-5 SOT23-5 Package Marking SABB*¢Z¢1¢X SABB*¢Z¢1¢X Supplied As Tape and Reel 250 Units, Tape and Reel 3000 Units, Tape and Reel
Pin Description
Pin # 1 Name ISET Function Programmable LED current Input. The LED current has the following relationship with the resistor used: RSET = 100 x (125 ÷ IOUT) 2 3 4 5 GND IOUT VIN EN Ground Connection Constant Current LED Output Power Supply Voltage Input. Input voltage range: 6V-12.6V Device Enable
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LM3590
Absolute Maximum Ratings
2)
(Notes 1,
Operating Conditions
Input Voltage Range EN Voltage Range Ambient Temperature (TA) Range (Note 4) Junction Temperature (TJ) Range 6.0V to 12.6V 0V to VIN -40°C to +85°C
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN EN Maximum Junction Temperature (TJMAX) Storge Temperature Maximum Lead Temperature (Soldering, 5 sec.) ESD Rating (Note 3) Human Body Model Machine Model 1.5kV 200V -0.3 to 13.0V Max -0.3 to (VIN+0.3V) w/ 13.0V max 150°C -65°C to +150°C 260°C
-40°C to +110°C
Thermal Information
Junction-to-Ambient Thermal Resistance, SOT23-5 Package (JA) (Note 5) 220°C/W
Electrical Characteristics (Notes 2, 6)
Limits in standard typeface are for TJ = 25°C and limits in boldface type apply over the full Operating Junction Temperature Range (-40°C TJ +110°C). Unless otherwise specified, CIN = 1 µF, VIN = 12.0V, VEN = 3.0V, RSET = 6.19k, VIOUT = 10.8V. Symbol IOUT Parameter Output Current Capability Conditions VIN = 12V 7.5V VIOUT 11.5V VIOUT = 10.8V 11.3V VIN 12.6V RSET = 8.35k RSET = 12.5k Output Current Programming IOUT ratio to ISET IQ Quiescent Supply Current 11.3V VIN 12.6V RSET = OPEN IOUT = OPEN VIN = 12.6V VEN = 0V IOUT = 95% nominal Min 19 (-5%) 19 (-5%) Typ 20 20 15 10 125 ÷ RSET 100:1 50 75 µA A Max 21 (+5%) 21 (+5%) mA Units
ISD VISET VHR
Shutdown Supply Current ISET Reference Voltage Minimum Current Source Voltage Headroom (VIN - VIOUT)(Note 7) Logic Input EN: High level Logic Input EN: Low level Enable Pin Input Current(Note 8) Turn-On Time
0.1 1.25 300
1
µA V mV
VIH VIL IEN tON
1.1 0 6 IOUT = 90% of steady state 50
VIN 0.3
V V µA µs
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical Characteristics table. Note 2: All voltages are with respect to the potential at the GND pin. Note 3: The human-body model is a 100pF capacitor discharged through a 1.5k resistor into each pin. The machine model is a 220pF capacitor discharged directly into each pin. Note 4: Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-OP = 110oC), the maximum power dissipation of the device in the application (PD-MAX), and the junction-to-ambient thermal resistance of the part/package in the application (JA), as given by the following equation: TA-MAX = TJ-MAX-OP - (JA x PD-MAX). The ambient temperature operating rating is provided merely for convenience. This part may be operated outside the listed TA rating, so long as the junction temperature of the device does not exceed the maximum operating rating of 110oC. Note 5: Junction-to-ambient thermal resistance is highly application and board-layout dependent. In applications where high maximum power dissipation exists, special care must be paid to thermal dissipation issues. For more information on these topics, please refer to the Power Dissipation section of this datasheet.
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