MAX8723ETE+T Maxim Integrated Products, MAX8723ETE+T Datasheet - Page 12

• Manufacturer Part Number: MAX8723ETE+T
• Description: IC REG FOR LCD DISPLAY 16-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8723ETE+T

• Applications: Converter, LCD
• Voltage - Input: 6 ~ 13.2 V
• Number Of Outputs: 1
• Voltage - Output: 3.3V, 2 ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The step-down regulator of the MAX8723 supports both
fixed output and adjustable output. Connect FB to GND
to enable the 3.3V fixed-output voltage (Figure 1).
Connect a resistive voltage-divider between OUT and
GND with the center tap connected to FB to adjust the
output voltage (Figure 4). Choose RB to be between
5kΩ and 50kΩ, and solve for RA using the equation:
where V
Low-Cost, Internal-Switch, Step-Down
Regulator for LCD Displays
Figure
12
______________________________________________________________________________________
4. Typical Operating Circuit, Adjustable Output
FB
= 2V, and V
RA RB
=
1µF
OUT
V
VL = 5V/25mA
REF
×
= 2V/50µA
⎛
⎜
⎝
can vary from 2V to 3.6V.
0.22µF
Dual-Mode Feedback
V
V
OUT
FB
−
1
⎞
⎟
⎠
SEE TABLE 1 FOR COMPONENT SELECTION
VCC2
SHDN
VL
VCC
GND
REF
FSEL
I.C.
MAX8723
INL
PGND
OUT
BST
EXT
0.22µF
EP
LX
FB
IN
The FSEL input selects the internal oscillator switching
frequency. Table 3 shows the switching frequency
based on the FSEL connection. High-frequency
(1.5MHz) operation optimizes the application for the
smallest component size, trading off efficiency because
of higher switching losses. Low-frequency (500kHz)
operation offers the best overall efficiency at the expense
of component size and board space.
Table
FSEL
GND
VCC
REF
3. Frequency Selection
CMS03
TOSHIBA
0.1µF
L
C
IN
Frequency Selection (FSEL)
IN = 12V ±10%
SWITCHING FREQUENCY (kHz)
RA
RB
C
OUT
OUT
1500
1000
500