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BD1754HFN

Datasheet

TSZ02201-0G3G0C200060-1-2

9.NOV.2012 Rev.001

www.rohm.com

© 2012 ROHM Co., Ltd. All rights reserved.

TSZ22111･15･001

(5) Circuit example when driving a large current with only one LED powered on.

VIN

ISET

GND

Current

DAC

UPIC

6

EN

L2

L1

0.1µF

L4

L3

(When ILED-max =32mA)

120k

Ω

ILED=128mA

Cin

Figure 20. Circuit example when driving a large current with only one LED powered on.

This figure shows a circuit example when driving a large current through all of four channels with only one LED

powered on. By shorting out all the LED driver pins, in the example of using 120 k

mA x 4) can be driven. In this example, the brightness can be adjusted in 64 gradations with 2 mA step (0.5 mA

step/channel x 4 channels). For higher current values, using 60 k

into one of the LEDs. The power ON/OFF and the brightness of the LEDs are controlled through the EN pin in

accordance with the UPIC format.

(6)

Circuit example when making the eight LEDs available by connecting the two BD1754HFN drivers

VIN

ISET

GND

Current

DAC

UPIC

6

EN

L2

L1

0.1µF

L4

L3

(When ILED-max =32mA)

120k

Ω

ILED=32mA

VIN

ISET

GND

Current

DAC

UPIC

6

EN

L2

L1

L4

L3

(When ILED-max =32mA)

120k

Ω

ILED=32mA

0.1µF

Cin

Cin

Figure 21. Circuit example when making the eight LEDs available by connecting the two BD1754HFN drivers

This figure shows a circuit example when making eight LEDs available by connecting two BD1754HFN drivers.

By connecting the control signals to the EN pins in parallel, the eight LED channels can be controlled concurrently.

This parallel connection scheme can increase the number of the LED channels further as necessary (such as twelve,

sixteen, or more). Determine the resistance value with which the LED current value is maximized and then connect

such resistor between the ISET and the GND pins. The power ON/OFF and the brightness of the LEDs are controlled

through the EN pin in accordance with the UPIC format.