AATIAN79 Datasheet, PDF (1/4 Pages) SiGe Semiconductor, Inc. – Single RGB Controller

EV-131
AAT4295 EVAL: Single RGB Controller
Introduction
The AAT4295 EVAL board demonstrates the operation of the AAT4295 SmartSwitch™. This device has three
low side N-channel load switches which are serially controlled. The AAT4295 operates from 1.8V to 5.5V, mak-
ing it ideal for use in 2.5V, 3.3V, or 5V systems as well as systems powered by lithium-ion/polymer batteries.
For demonstration purposes, an AAT3110 voltage doubling charge pump has been incorporated to provide a
regulated voltage source to power the system load, which is an RGB LED.
The AAT4295 is controlled by an S²Cwire™ (Simple Serial Control™) interface with easy control and efficiency.
The device is enabled with the desired switch configuration after a short set of data pulses is sent to the
EN/SET input and holding the line pulled to a logic high. In the enabled state, the AAT4295 typically consumes
less than 3µA of quiescent current. When EN/SET is pulled to a logic low, the device is disabled and each out-
put switch is placed in a high impedance open state. The switch resistance of the low side N-channel MOS-
FET switches is approximately 2Ω.
This document describes the evaluation board and its accompanying user interface. In addition, a brief
“Getting Started” section is included to help the user begin operating the evaluation board. A schematic of the
complete circuit and the actual board layout are also included in the documentation. For additional informa-
tion, please consult the AAT4295 product datasheet.
Schematic
R9 R10 R11 R12 R13
1K 1K 1K 1K 1K
024 ₁₃₅ ^SW1
024 ₁₃₅ ^SW2
024 ₁₃₅ ^SW3
024 ₁₃₅ ^SW4
024 ₁₃₅ ^SW5
U3
1
2
3
4
VDD
GP5
GP4
GP3
VSS
GP0
GP1
GP2
8
7
6
5
PIC12F675
C3
10µF
VCC
C1
1µF
U1
1
2
3
4
VOUT C+
GND VIN
GND C-
GND SHDN
8
7
6
5
AAT3110
2.7V - 5V
Off On DC+
DC-
321
J1
C2
1µF
VCC
100K
R8
C4
10µF
V_{CC R7}
100K
BG R
RGB 1 _{D3 D2 D1}
BG R
D6 D5 D4
RGB 2
U2
1
2
3
4
VIN
N/C
N/C
EN
OUT3
OUT2
OUT1
GND
8
7
6
5
AAT4295
R3 R2 R1
70 68 130
R6 R5 R4
70 68 130
Figure 1: Evaluation Board Schematic.
EV-131.2007.01.1.0
1