MAX8678 Maxim Integrated Products, MAX8678 Datasheet
MAX8678
Manufacturer Part Number
MAX8678
Description
White LED Charge Pump
Manufacturer
Maxim Integrated Products
Datasheet
1.MAX8678.pdf
(13 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
MAX8678ETE
Manufacturer:
MAXIM
Quantity:
392
Company:
Part Number:
MAX8678ETE+T
Manufacturer:
HIROSE
Quantity:
9 823
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The MAX8678 integrates a charge pump for white light-
emitting diodes (LEDs) with an audio loudspeaker
amplifier. The high-efficiency, adaptive charge pump
drives up to four LEDs with constant current for uniform
brightness. The LED current is adjustable from
0.1mA/LED to 24mA/LED in 31 pseudo-logarithmic
steps through a single-wire serial-pulse interface. High
accuracy and LED-to-LED current matching are main-
tained throughout the adjustment range. Individual
adaptive mode switching for each LED provides high
efficiency with a wide range of LED forward voltages.
The mono class AB audio amplifier directly drives an 8Ω
loudspeaker with 1.1W RMS continuous power from a 5V
supply with less than 1% THD+N. The gain is adjustable
from -9dB to +18dB in ten 3dB steps through a single-
wire serial-pulse interface. Clicks and pops are sup-
pressed during on/off and all gain adjustments.
Differential inputs improve common-mode noise rejection.
The MAX8678 includes soft-start, thermal shutdown,
open-circuit and short-circuit protection, and is avail-
able in the 16-pin, 3mm x 3mm Thin QFN package
(0.8mm max height).
19-0786; Rev 0; 4/07
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
DIFFERENTIAL
2.7V TO 5.5V
AND DIMMING
AMP ON/OFF
LED ON/OFF
AND GAIN
INPUT
Cell Phones and Smartphones
Camera Phones
PDAs, Digital Cameras, Camcorders
AUDIO
INPUT
4.7μF
Typical Operating Circuit
IN
ENLED
ENAMP
GND
A+
A-
________________________________________________________________ Maxim Integrated Products
C+
EP
MAX8678
General Description
1μF
NEG
C-
OUT+
LED1
LED2
LED3
LED4
OUT-
BIAS
1μF
Applications
0.1μF
LOUDSPEAKER
8Ω
0.1mA TO
24mA
BACKLIGHT
OR FLASH
White LED Charge Pump with
♦ High-Efficiency White LED Charge Pump
♦ Mono Class AB Audio Amplifier
♦ Soft-Start Limits Inrush Current
♦ Thermal Shutdown, Open- and Short-Circuit
♦ 16-Pin, 3mm x 3mm Thin QFN Package
+ Denotes a lead-free package.
Note: The device is specified over the -40°C to +85°C extend-
ed temperature range.
MAX8678ETE+
Protection
TOP VIEW
PART
1.1W Audio Amplifier
Individual Adaptive Supply for Each LED
4 Low-Dropout LED Current Regulators
24mA to 0.1mA Dimming Range
Single-Wire, Serial-Pulse Dimming Interface
1% (typ) Accuracy
Low 140µA Quiescent Current
1.1W RMS Mono BTL Output (8Ω, V
Low 0.004% THD+N at 1kHz
High 90dB PSRR at 1kHz
Fully Differential Inputs
-9dB to +18dB Gain Settings in 3dB Steps
Integrated Click/Pop Suppression
Low Quiescent Current
ENLED
NEG
C+
C-
13
14
15
16
PIN-PACKAGE
16 Thin QFN
3mm x 3mm
+
12
1
Ordering Information
3mm × 3mm
THIN QFN
MAX8678
11
2
Pin Configuration
10
3
TOP MARK
AFF
9
4
Features
IN
8
7
6
5
= 5V)
PKG CODE
BIAS
OUT-
OUT+
ENAMP
T1633-5
1