Ultra-Efficient Charge Pumps for
Six White/RGB LEDs in 3mm x 3mm Thin QFN
7/MAX648
ELECTRICAL CHARACTERISTICS (continued)
(V
= V = 3.6V, V
= 0V, T = -40°C to +85°C, unless otherwise noted. Typical values are at T = +25°C.) (Note 1)
GND A A
VDD
IN
PARAMETER
CONDITIONS
MIN
TYP
MAX
0.40
400
UNITS
V
SDA Output Low Voltage
I
= 3mA, for acknowledge (Note 2)
0.03
SDA
2
I C Clock Frequency
kHz
Bus Free Time Between START and
STOP (t
(Note 2)
(Note 2)
1.3
0.6
µs
µs
)
BUF
Hold Time Repeated START Condition
(t
0.1
)
HD_STA
SCL Low Period (t
)
(Note 2)
(Note 2)
1.3
0.6
0.2
0.2
µs
µs
LOW
SCL High Period (t
)
HIGH
Setup Time Repeated START
(Note 2)
0.6
0.1
µs
Condition (t
)
SU_STA
SDA Hold Time (t
)
(Note 2)
(Note 2)
0
-0.01
50
µs
ns
HD_DAT
SDA Setup Time (t
)
100
SU_DAT
Setup Time for STOP Condition
(t
(Note 2)
0.6
0.1
µs
)
SU_STO
SERIAL-PULSE LOGIC (EN_) (MAX8648)
Logic-Input High Voltage
Logic-Input Low Voltage
V
V
= 2.7V to 5.5V
= 2.7V to 5.5V
1.4
-1
V
V
IN
IN
0.4
+1
T
T
= +25°C
= +85°C
0.01
0.1
A
Logic-nput Current
V
= 0V or V = 5.5V
µA
IL
IH
A
t
t
t
(Figure 3)
Time from EN_ held low to I
= 0mA
LED_
4
ms
µs
µs
µs
SHDN
(Figure 3)
1
1
500
LO
HI
(Figure 3)
Initial t (Figure 3)
HI
First EN_ high pulse
120
CHARGE PUMP
Switching Frequency
1
MHz
ms
V
Soft-Start Time
0.5
5.0
2.5
Charge-Pump Regulation Voltage
Open-Loop NEG Output Resistance
(V - V
)
4.3
IN
NEG
(V
NEG
- 0.5 x V ) / I
NEG
5
Ω
IN
NEG Discharge Resistance in
Shutdown or When the Charge Pump
is Inactive
All LEDs off, EN_ = GND
2
10
kΩ
mA
%
LED1–LED6 CURRENT REGULATOR
Current Setting Range
Through an I C or serial-pulse interface
0.1
-2
24.0
+2
24mA setting, T = +25°C
1
5
A
V
= 0.5V for
LED_
24mA setting, T = -40°C
A
to derating function start
temperature (Note 2)
charge-pump inactive,
Current Accuracy
-5
+5
V
V
= -0.9V,
= -1.4V
LED_
NEG_
1.6mA setting, T = +25°C
-15
+15
A
_______________________________________________________________________________________
3
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
