EL7640, EL7641, EL7642
Typical Performance Curves (Continued)
INPUT
VOLTAGE
INPUT
V
BOOST
OUTPUT
V
ON
V
OFF
C
=220nF
DEL
TIME (50µs/DIV)
TIME (20ms/DIV)
FIGURE 13. START-UP SEQUENCE
FIGURE 14. OP AMP RAIL-TO-RAIL INPUT/OUTPUT
JEDEC JESD51-7 HIGH EFFECTIVE
THERMAL CONDUCTIVITY TEST BOARD -
QFN EXPOSED DIEPAD SOLDERED TO
JEDEC JESD51-3 AND SEMI G42-88
(SINGLE LAYER) TEST BOARD
PCB PER JESD51-5
0.8
3
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
2.857W
2.5
2
758mW
QFN32
QFN32
=35°C/W
θ
=125°C/W
JA
θ
JA
1.5
1
0.5
0
0
25
50
75 85 100
125
150
0
25
50
75 85 100
125
150
AMBIENT TEMPERATURE (°C)
AMBIENT TEMPERATURE (°C)
FIGURE 15. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
FIGURE 16. PACKAGE POWER DISSIPATION vs AMBIENT
TEMPERATURE
TABLE 1. RECOMMENDED COMPONENTS
Applications Information
The EL7640, EL7641, EL7642 provide a highly integrated
multiple output power solution for TFT-LCD applications.
The system consists of one high efficiency boost converter
DESIGNATION
DESCRIPTION
C , C , C
10µF, 16V X5R ceramic capacitor (1210)
TDK C3216X5R0J106K
1
2
3
and two low cost linear-regulator controllers (V
and
ON
) with multiple protection functions. The block diagram
of the whole part is shown in Figure 17. Table 1 lists the
recommended components.
D
1A 20V low leakage schottky rectifier
(CASE 457-04)
ON SEMI MBRM120ET3
1
V
OFF
D
, D , D
200mA 30V schottky barrier diode (SOT-23)
Fairchild BAT54S
11 12 21
The EL7640, EL7641, EL7642 integrate an N-channel
MOSFET in boost converter to minimize the external
L
6.8µH 1.3A Inductor
TDK SLF6025T-6R8M1R3-PF
1
component counts and cost. The V , V
linear-
regulators are independently regulated by using external
ON OFF
Q
200mA 40V PNP amplifier (SOT-23)
Fairchild MMBT3906
11
21
resistors. To achieve higher voltage than V
multiple stage charge pumps may be used.
, one or
BOOST
Q
200mA 40V NPN amplifier (SOT-23)
Fairchild MMBT3904
FN7415.1
September 26, 2005
9
INTERSIL [ Intersil ]
