AAT2847
Four-Channel Backlight Driver with Dual LDOs
Electrical Characteristics
1
V
IN
= 3.6V; C
IN
= C
LDOA
= C
LDOB
= 2.2µF; C
OUT
= 1µF; C1 = C2 = 1µF; T
A
= 25°C, unless otherwise noted.
Typical values are at T
A
= 25°C.
Symbol
V
IN
I
SHDN
Charge Pump
1x Mode, 3.0
≤
V
IN
≤
5.5, Active, No Load,
V
ENA
= V
ENB
= 0V
I
IN
Input Operating Current
1.5x Mode, 3.0
≤
V
IN
≤
5.5, Active, No
Load, V
ENA
= V
ENB
= 0V
2x Mode, 3.0
≤
V
IN
≤
5.5, Active, No Load,
V
ENA
= V
ENB
= 0V
DATA 1, 20mA Range
I
DX
Average Current Accuracy
DATA 2, ADDRESS 4
DATA 1, 30mA Range
DATA 1, 15mA Range
V
IN
- V
F
= 1.5V, 20mA Range
18
0.9
20
1.0
30
15
0.5
150
1
140
15
1
%
mV
MHz
˚C
˚C
1.0
4.0
5.0
22
1.1
mA
mA
Description
Input Voltage Range
Total Shutdown Current at IN
Conditions
Min Typ Max Units
2.7
5.5
1.0
V
µA
Power Supply
V
EN/SET
= V
ENA
= V
ENB
= 0V
I
(D-Match)
V
TH
f
CLK
T
SD
T
HYS
Current Matching
2
1x to 1.5x or 1.5x to 2x Transition
20mA Range
Threshold at Any DX Pin
Clock Frequency
Over-Temperature Shutdown
Threshold
Over-Temperature Shutdown
Hysteresis
EN/SET Low Time
0.3
EN/SET Logic Control
T
EN/SET LO
75
50
75
500
500
0.4
1.4
V
EN/SET
= V
IN
= 5V
-1
1
µs
ns
µs
µs
µs
V
V
µA
T
EN/SET_HI_MIN
Minimum EN/SET High Time
T
EN/SET_HI_MAX
Maximum EN/SET High Time
T
OFF
T
LAT
V
IL(EN/SET)
V
IH(EN/SET)
I
EN/SET
EN/SET Off Timeout
EN/SET Latch Timeout
EN/SET Logic Low Threshold
Voltage
EN/SET Logic High Threshold
Voltage
EN/SET Input Leakage
1. The AAT2847 is guaranteed to meet performance specifications over the –40˚C to +85°C operating temperature range is assured by
design, characterization and correlation with statistical process controls.
2. Current matching is defined as the deviation of any sink current from the average of all active channels.
4
2847.2007.09.1.0
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
