Datasheet
RoHS Compliance Information
| Size in Kbytes | Date |
 |
| LM27953 White LED Driver with Four LED Current Sinks and 3/2x Switched Capacitor Boost |
681
Kbytes |
18-Nov-04 |
Download |
LM27953 White LED Driver with Four LED Current Sinks and 3/2x Switched Capacitor Boost (Japanese)
 |
413 Kbytes |
|
 |
Package Availability, Models, Samples & Pricing
| Obsolete Part | Alternate Part or
Supplier | Source | Last Time Buy Date |
LM27953TL
| LM2796
| National Semiconductor
| 30 Nov 2009
|
LM27953TLX
| LM2796
| National Semiconductor
| 30 Nov 2009
|
General Description
The LM27953 is a charge-pump-based white-LED driver that is ideal for mobile phone display backlighting. It is intended to drive 4 LEDs for a main phone display backlight. Regulated internal current sources deliver excellent current and brightness matching in all LEDs.
The LED driver current sinks can be used to backlight a main phone display with up to 4 LEDs. The low-side current drivers accommodate common-anode-type LEDs. The current sinks can also drive standard two-terminal LEDs, and provide other general lighting functions (keypad lighting, fun lighting, etc). The brightness of the LEDs can be adjusted independently with an external resistor.
The LM27953 works off an extended Li-Ion input voltage range (2.7V to 5.5V). Voltage boost is achieved with a high-efficiency 3/2×-gain charge pump.
The LM27953 is available in National's chip-scale 18-bump micro SMD package.
Reliability Metrics
| Part Number |
Process |
EFR Reject |
EFR Sample Size |
PPM |
LTA Rejects |
LTA Device Hours |
FITS |
MTTF (Hours) |
|
LM27953TL | CS065 | 2 | 38968 | 52 | 0 | 4402000 | 1 | 1249079519
|
|
LM27953TLX | CS065 | 2 | 38968 | 52 | 0 | 4402000 | 1 | 1249079519
|
Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR.
The Long Term Failure Rates were calculated
at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress
temperature of 150°C to an application temperature of 55°C.
For more information on Reliability Metrics, please click here.
More Application Notes
| Title | Size in Kbytes |
Date |
|
| AN-1218: Application Note 1218 LM2791/2/4/5 Evaluation Board |
424
Kbytes |
13-May-04 |
Download |
| AN-1251: Application Note 1251 Switched Capacitor Circuits Provide Efficient and Functional White LED Drive |
55
Kbytes |
26-Sep-02 |
Download |
[Information as of 8-Nov-2009]
|
