AAT3151
High Efficiency 1X/1.5X/2X Charge Pump
For White LED Applications
Electrical Characteristics
1
C
IN
= C
OUT
= C
1
= C
2
= 1.0µF; T
A
= -40°C to +85°C, unless otherwise noted.
Typical values are T
A
= 25°C, V
IN
= 3.5V.
Symbol
Description
Conditions
Min
2.7
1X Mode, 3.0
≤
V
IN
≤
5.5, Active,
No Load Current
1.5X Mode, 3.0
≤
V
IN
≤
5.5, Active,
No Load Current
2X Mode, 3.0
≤
V
IN
≤
5.5, Active,
No Load Current
50µA Setting, 1X Mode
EN/SET = 0
I
SET
= 30mA, T
A
= 25°C
V
F
:D1:D4 = 3.6V
0.3
1
2.0
50
27
30
0.5
150
1
33
Typ
Max
5.5
1
3
3.7
Units
V
Input Power Supply
V
IN
Operation Range
I
CC
Operating Current
mA
Shutdown Current
I
SINK
Current Accuracy
2
I
(D-Match)
Current Matching Between Any
Two Current Sink Inputs
3, 4
V
TH
1X to 1.5X or 1.5X to 2X Transition I
SET
= 20mA
Threshold at Any I
SINK
Pin
Charge Pump Section
T
SS
Soft-Start Time
F
CLK
Clock Frequency
EN/SET
V
IL
Enable Threshold Low
V
IN
= 2.7V
V
IH
Enable Threshold High
V
IN
= 5.5V
T
EN/SET LO
EN/SET Low Time
T
EN/SET_HI_MIN
Minimum EN/SET High Time
T
EN/SET_HI_MAX
Maximum EN/SET High Time
T
OFF
EN/SET Off Timeout
5
T
LAT
EN/SET Latch Timeout
6
I
EN/SET
EN/SET Input Leakage
I
SHDN
I
DX
µA
µA
mA
%
mV
100
1000
0.4
1.4
0.3
50
75
500
500
1
75
µs
kHz
V
V
µs
ns
µs
µs
µs
µA
-1
1. The AAT3151 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured
by design, characterization, and correlation with statistical process controls.
2. Determined by the average of all active channels.
3. Current matching is defined as the deviation of any sink current at I
OUT
= 20mA and 2mA.
4. Specification applies only to the tri-mode charge pump.
5. The EN/SET pin must remain logic low (less than V
IL
) for the duration of longer than 500µs to guarantee the off timeout.
6. The EN/SET pin must remain logic high (greater than V
IH
) for the duration of longer than 500µs to guarantee the latch timeout.
4
3151.2005.12.1.7
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
