Diodes AL3157 - Manual (Page 3)

AL3157
HIGH EFFICIENCY 1x/2x CHARGE PUMP LED DRIVER
FOR SMALL SCREEN BACKLIGHTING AND FLASHLIGHT
AL3157
Document number: DS35116 Rev. 1 - 2
3 of 9
www.diodes.com
March 2011
© Diodes Incorporated
N
E
W
PRODUC
T
Absolute Maximum Ratings (Note 2)
Symbol Description Rating Unit
ESD HBM Human Body Model ESD Protection 2 kV
ESD MM Machine Model ESD Protection 200 V
V
IN
Input Voltage -0.3 to 6 V
V
EN1,2,3
EN1, EN2, EN3 to GND Voltage -0.3 to V
IN
+0.3 V
I
OUT
Maximum DC Output Current 300 mA
T
J
Operating Junction Temperature Range 125 °C
T
LEAD
Maximum Soldering Temperature (at leads, 10 sec) 300
°C
Notes: 2. Exceeding Absolute Maximum Ratings will cause permanent damage to the device.
Recommended Operating Conditions
Symbol Parameter Min Max Unit
V
IN
Input Voltage 2.7 5.5 V
V
ENL(1, 2)
EN1,2 Threshold Low 0 0.4 V
V
ENH(1,2)
EN1,2, Threshold High 1.4 V
IN
V
T
A
Operating Ambient Temperature -40 85 °C
Electrical Characteristics
V
IN
= 4V, C
IN
= C
OUT
= 2.2µF, C
1
= 1µF; T
A
= 25°C unless otherwise noted.
Symbol Parameter Test Conditions Min Typ. Max Unit
I
Q
Quiescent Current
1x Mode, 3.0≤V
IN
≤5.5, Active,
No Load Current
0.3 0.6
mA
2x Mode, 3.0≤V
IN
≤5.5, Active,
No Load Current
2 5
I
SHDN
Shutdown Current EN1, EN2 = 0 1 µA
I
D2~4
Backlight LED Drive Sink Current
Accuracy (Note 3)
I
DX
= 30mA 28.5 30 31.5 mA
I
D1
Flash/light LED Drive Sink Current
Accuracy (Note 3)
I
D1
= 210mA 199.5 210 220.5 mA
I
D-Match
Current Matching Between Any
Two Backlight LED Drive Current
Sink Outputs (Note 4)
V
F
: D2:D4 = 4V 1 2 %
R
out
Charge Pump V
OUT
Open Loop
Resistance
1x mode 0.5
Ω
2x mode 4.5
V
TH-Dx
1x to 2x Transition Threshold at
D2, D3 and D4 Pins
I
D
= 30mA 150 mV
V
TH-D1
1x to 2x Transition Threshold at D1
Pin
I
D1
= 210mA 150 mV
V
HS
Mode Transition Threshold 500 mV
t
SS
Soft-Start Time 100 µs
f
SW
Switching Frequency 1.2 MHz
t
EN1,2
EN1,2 Off Timeout 20 ms
UVLO V
IN
Under-Voltage Lockout 1.8 2 2.2 V
I
EN1,2
EN1, 2 Input Leakage -1 1 µA
T
SHDN
Thermal Shutdown Protection 160 o C
T
HYS
Thermal Shutdown Hysteresis 10
o
C
θ
JA
Thermal Resistance
Junction-to-Ambient
U-DFN3030-12 (Note 5) 55.29 o C/W
Notes: 3. Determined by the mean of channels 2,3 and 4 currents, EG (I D2 + I D3 + I D4 )/3
4. Determined by the maximum sink current (MAX), the minimum sink current (MIN), and the average sink current (AVG). Two matching
numbers are calculated as (MAX-AVG)/AVG and (AVG-MIN)/AVG. The largest number of the two (worst case) is as the matching data.
5. Device mounted on FR-4 substrate, 2"*2", 2oz, copper, double-sided PC board.