AP8804

AP8804

Document number: DS32050 Rev. 2 - 5

7 of 9

www.diodes.com

February 2010

© Diodes Incorporated

A Product Line of

Diodes Incorporated

PCB Layout and Supply Conditioning

For a satisfactory pulse shape and AC stability, attention should be given to power supply decoupling. Connect a 0.1µF to 1µF

X7R ceramic capacitor from Vcc to the common ground plane close to the Vcc pin. Position the capacitor close to the VCC pin

and use local vias to ground the capacitor. Additional ground vias should be placed as close as possible to the central paddle

connection for the sake of both the pulse performance and thermal heat-sinking. The ground plane is also required to minimize

undesired common-impedance coupling between input and output.

Excessive stray capacitance at the BIAS pin affects stability. It is sufficient to place the input bias resistor close to the BIAS pin to

minimize the PCB trace capacitance to ground.

The AP8804 has been designed to drive the cathode of a low voltage LED which has the anode connected to the same node as

VCC pin. Alternatively the anode may be connected to a higher voltage than VCC within the limits given. However best LED

current regulation will be obtained when the anode is connected to VCC.

Power Dissipation and Operating Temperature

Although the performance of the AP8804 is not significantly affected by junction temperature, excessive power dissipation does

affect the target output current. The typical variation of I_Out with power dissipation is approximately +0.065%/mW. A typical

remote control application uses an NEC protocol data-burst with a low impedance 3V supply and 1.6V drop (at 250mA) across the

LED load. Under these conditions, the power dissipation related error in I_Out will be approximately 3% average during the burst.

Ordering Information

Device

Package

Code

Packaging

7”/13” Tape and Reel

Quantity

Part Number

Suffix

AP8804SNG-7

SN

DFN2020-6

3000/ Tape & Reel

-7

Marking Information

A7 = Product Type Marking Code

Y = Year 0 ~ 9

W = Week: A ~ Z : 1 ~ 26 Week;

a ~ z : 27 ~ 52 week;

z represents 52 and 53 week

A7

Y W X