ADM8845 Ver la hoja de datos (PDF) - Analog Devices

Número de pieza

componentes Descripción

Fabricante

ADM8845

Charge Pump Driver for LCD White LED Backlights

Analog Devices 

PIN CONFIGURATION AND FUNCTION DESCRIPTION

ADM8845

VOUT 1

C2+ 2

ISET 3

FB1 4

PIN 1

INDICATOR

ADM8845

TOP VIEW

(Not to Scale)

12 CTRL2

11 C2–

10 GND

9 FB6

Figure 2. Pin Configuration

Table 3. Pin Function Descriptions

Pin No. Mnemonic Function

1

VOUT

Charge Pump Output. A 2.2 µF capacitor to ground is required on this pin. Connect VOUT to the anodes of all

the LEDs.

2

C2+

Flying Capacitor 2 Positive Connection.

3

ISET

Bias Current Set Input. The current flowing through RSET, ISET, is gained up by 120 to give the ILED current.

Connect RSET to GND to set the bias current as VSET/RSET. Note that VSET = 1.18 V.

4–9

FB1–FB6

LED1–LED6 Cathode Connection and Charge Pump Feedback. The current flowing in these LEDs is 120 times

the current flowing through RSET, ISET. When using fewer than six LEDs, this pin can be left unconnected or

connected to GND.

10

GND

Device Ground Pin.

11

C2−

Flying Capacitor 2 Negative Connection.

12

CTRL2

Digital Input. 3 V CMOS Logic. Used with CTRL1 to control the shutdown operation of the main and sub LEDs.

13

CTRL1

Digital Input. 3 V CMOS Logic. Used with CTRL2 to control the shutdown operation of the main and sub LEDs.

14

C1−

Flying Capacitor 1 Negative Connection.

15

VCC

Positive Supply Voltage Input. Connect this pin to a 2.6 V to 5.5 V supply with a 4.7 µF decoupling capacitor.

16

C1+

Flying Capacitor 1 Positive Connection.

-

EP

Expose Paddle. Connect the exposed paddle to GND.

Rev. 0 | Page 5 of 20

Share Link: