LT3950 Demo Board | 60V 1.5A LED Driver with Internal Log-Scale Dimming
Analog Devices Inc.
Demonstration circuit 2788A is a boost LED driver featuring the LT®3950. This demonstration circuit powers a string of LEDs at 330mA. The step-up topology can be used to drive a string of up to 28V of LEDs as assembled. The maximum output voltage capability of the LT3950 is 60V. DC2788A runs from an input voltage range of 6V to 24V as built. It also runs at 2MHz and has the capability to turn on spread spectrum frequency modulation (SSFM) for a frequency range of 2.0MHz to 2.5MHz. Dimming control can be achieved with analog dimming or PWM dimming—either from an external or internally-generated clock source. DC2788A features undervoltage lockout (UVLO) set at 6.6V with a 1.0V hysteresis for turn-on.
The UVLO voltage, LED current, output voltage range, switching frequency, brightness control, SSFM, and the topology can all be adjusted with simple modifications to
the demonstration circuit.
LT3950 is a monolithic 1.5A peak switch current, 60V LED driver. The guaranteed peak switch current rating of the IC is 1.5A and this is important to know when calculating maximum output current at a given LED voltage and input voltage for a boost converter. The LT3950 features SSFM and a well-controlled SW node for low emissions.
A frequency range of 200kHz to 2MHz and a high-side PWMTG PWM-dimming MOSFET makes this a very versatile IC for many applications. It can be used for boost,
buck-boost mode and buck mode LED driver applications. The PWMTG MOSFET not only provides high PWM dimming ratio capability, but it also serves as a short-circuit
protection device. The FAULT flag indicates when there is either a short-circuit or open-LED fault at the output.
The demo circuit is designed to be easily reconfigured to suit other applications, including the example schematics in the data sheet. Consult technical support for assistance.
High voltage operation, 3V input voltage operation, multiple topologies, small-and-compact size, fault protection, low EMI, and multiple brightness control options make
the LT3950 flexible and powerful for compact, noise-sensitive LED driver solutions. The LT3950JMSE featured on this demo circuit is available in a thermally enhanced
16-lead plastic MSOP package. The LT3950 data sheet must be read in conjunction with this demo manual to properly use or modify demo circuit DC2788A.
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | 505-DC2788A-ND | 1 | 1 | $110.80 | $110.80 | $110.80 | $110.80 | $110.80 | $110.80 |
| Analog Devices Inc | DC2788A | 0 | $110.35 | $110.35 | $110.35 | $110.35 | $110.35 | $110.35 | |
| Arrow North American Components | DC2788A | 0 | 1 | $102.92 | $102.92 | $102.92 | $102.92 | $102.92 | $102.92 |
| element14 APAC | DC2788A | 1 | 1 | * $119.25 | * $119.25 | * $119.25 | * $119.25 | * $119.25 | * $119.25 |
| Farnell | DC2788A | 1 | 1 | * $115.05 | * $115.05 | * $115.05 | * $115.05 | * $115.05 | * $115.05 |
| Mouser Electronics | 584-DC2788A | 4 | 1 | $114.78 | $114.78 | $114.78 | $114.78 | $114.78 | $114.78 |
| Newark | DC2788A | 1 | 1 | $110.80 | $110.80 | $110.80 | $110.80 | $110.80 | $110.80 |
| Verical Marketplace | DC2788A | 10 | 1 | $109.19 | $109.19 | $109.19 | $109.19 | $109.19 | $109.19 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | AD9883ABSTZ-110-ND | 0 | 1 | $23.33 | $17.14 | $15.55 | $15.55 | $15.55 | $15.55 |
| Analog Devices Inc | AD9883ABSTZ-110 | 0 | $21.05 | $19.42 | $18.54 | $18.54 | $18.54 | $18.54 | |
| Mouser Electronics | 584-AD9883ABSTZ-110 | 0 | 1 | $16.00 | |||||
| Newark | AD9883ABSTZ-110 | 0 | $15.09 | $13.72 | $11.97 | $11.97 | $11.97 | $11.97 | |
| Win Source | AD9883ABSTZ-110 | 9400 | 3 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | MAX6955EVKIT | 0 | 1 | $108.58 | $108.58 | $108.58 | $108.58 | $108.58 | $108.58 |
| Farnell | MAX6955EVKIT | 0 | 1 | * $118.34 | * $118.34 | * $118.34 | * $118.34 | * $118.34 | * $118.34 |
| Mouser Electronics | MAX6955EVKIT | 0 | 1 | $112.41 | $112.41 | $112.41 | $112.41 | $112.41 | $112.41 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | MAX6964EVKIT | 0 | 1 | $82.88 | $82.88 | $82.88 | $82.88 | $82.88 | $82.88 |
| Arrow North American Components | MAX6964EVKIT | 0 | 1 | $77.83 | $77.06 | $75.52 | $74.77 | $72.55 | $71.82 |
| Farnell | MAX6964EVKIT | 0 | 1 | * $89.67 | * $89.67 | * $89.67 | * $89.67 | * $89.67 | * $89.67 |
| Mouser Electronics | MAX6964EVKIT | 1 | 1 | $85.16 | $85.16 | $85.16 | $85.16 | $85.16 | $85.16 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | MAX8571EVKIT | 0 | 1 | $94.37 | $94.37 | $94.37 | $94.37 | $94.37 | $94.37 |
| Farnell | MAX8571EVKIT | 0 | 1 | * $102.46 | * $102.46 | * $102.46 | * $102.46 | * $102.46 | * $102.46 |
| Mouser Electronics | MAX8571EVKIT | 0 | 1 | $97.33 | $97.33 | $97.33 | $97.33 | $97.33 | $97.33 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | MAX6951EVKIT | 0 | 1 | $112.07 | $112.07 | $112.07 | $112.07 | $112.07 | $112.07 |
| Farnell | MAX6951EVKIT | 0 | 1 | * $122.26 | * $122.26 | * $122.26 | * $122.26 | * $122.26 | * $122.26 |
| Mouser Electronics | MAX6951EVKIT | 5 | 1 | $116.12 | $116.12 | $116.12 | $116.12 | $116.12 | $116.12 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | MAX3740AETG-T-ND | 0 | 2500 | $5.08 | |||||
| Arrow North American Components | MAX3740AETG+T | 0 | 2500 | $10.38 | |||||
| Mouser Electronics | 700-MAX3740AETG-T-NR | 0 | 1 |
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | MAX3669EHJ-T-ND | 0 | 2500 | $7.49 | $7.49 | $7.49 | $5.98 | ||
| Mouser Electronics | 700-MAX3669EHJ-NR | 0 | 1 |
Evaluating the ADP8861 Charge Pump, 7-Channel Smart LED Driver with I2C Interface
Analog Devices Inc.
The ADP8860SHIELD-EVALZ and the ADP8861SHIELD-EVALZ incorporate light emitting diodes (LEDs) for quick and easy evaluation of the ADP8860 and the ADP8861. Note that only the ADP8860SHIELD-EVALZ has dual light intensity sensors. The ADP8860SHIELD-EVALZ and the ADP8861SHIELD-EVALZ follow the form factor of a regular Arduino® shield to allow compatibility with microcontroller boards that use the same interface. These evaluation boards also incorporate a separate header dedicated to I2C communications.
The ADP8860 and the ADP8861 are 7-channel LED drivers that utilizes a charge pump with selective gain for maximum efficiency. The LEDs driven by either device are programmable for maximum current and fade in and out times via the I2C interface. Only the ADP8860 has a programable light intensity threshold that can be set via the I2C interface of the device. Each channel can handle up to 30 mA (typical), except for the seventh channel, which can handle 60 mA (typical). Each channel can be unified to have the same fade in time and fade out time, or each channel can have an individual fade in time and fade out time for greater flexibility.
For full details on the ADP8860 and the ADP8861, see the ADP8860 and the ADP8861 data sheets, which should be consulted in conjunction with the user guide when using these evaluation boards.
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | 505-ADP8861SHIELD-EVALZ-ND | 0 | 1 | $86.53 | $86.34 | $86.34 | $86.34 | $86.34 | $86.34 |
| Analog Devices Inc | ADP8861SHIELD-EVALZ | 0 | $85.60 | $85.60 | $85.60 | $85.60 | $85.60 | $85.60 | |
| Arrow North American Components | ADP8861SHIELD-EVALZ | 4 | 1 | $23.04 | $23.04 | $23.04 | $23.04 | $23.04 | $23.04 |
| Mouser Electronics | 584-ADP8861SHIELDEVA | 5 | 1 | $89.04 | $89.04 | $89.04 | $89.04 | $89.04 | $89.04 |
| Verical Marketplace | ADP8861SHIELD-EVALZ | 64 | 1 | $84.70 | $84.70 | $84.70 | $84.70 | $84.70 | $84.70 |
LTC3219EUD Demo Board | 9-Channel Charge Pump LED Driver, 2.9V ≤ VIN ≤ 5.5V, VLED = up to 5V @ 28mA per LED (DC590 Requires)
Analog Devices Inc.
Demonstration circuit 1055 is a 250mA Universal Nine Channel Multimode (1x, 1.5x, 2x) Charge Pump LED Driver with two RGB displays and three white LEDs featuring the LTC3219. The LTC3219 is a low noise charge pump designed to drive nine universal LED current sources. The input voltage range is 2.9V to 5.5V. Each channel provides 28mA of LED current.
The LTC3219 requires only five small ceramic capacitors to form a complete LED power supply and current controller. The maximum display currents are set with an internal precision current reference. On/Off blinking, gradation, and intensity are achieved via an I2C serial interface. There are 64 dimming states available for the universal LEDs. The DC590 controller board is required for proper operation.
| Distributor | SKU | Stock | MOQ | 1 | 10 | 50 | 100 | 1,000 | 10,000 |
|---|---|---|---|---|---|---|---|---|---|
| DigiKey | DC1055A-ND | 0 | 1 | $110.51 | $110.51 | $110.51 | $110.51 | $110.51 | $110.51 |
| Analog Devices Inc | DC1055A | 0 | $100.05 | $100.05 | $100.05 | $100.05 | $100.05 | $100.05 | |
| Mouser Electronics | 584-DC1055A | 5 | 1 | $114.46 | $114.46 | $114.46 | $114.46 | $114.46 | $114.46 |
| Newark | DC1055A | 0 | 1 | $133.39 | $133.39 | $133.39 | $133.39 | $133.39 | $133.39 |





