MAX5073ETI Maxim Integrated Products, MAX5073ETI Datasheet - Page 8

• Manufacturer Part Number: MAX5073ETI
• Description: DC/DC Switching Converters 2.2MHz Buck or Boost Converter
• Manufacturer: Maxim Integrated Products

2.2MHz, Dual-Output Buck or Boost Converter
with Internal Power MOSFETs
(V+ = VL = 5.2V, T
8
_______________________________________________________________________________________
PIN
3, 4
1
2
5
6
7
8
9
3.00
2.75
2.50
2.25
2.00
1.75
1.50
1.25
1.00
BST2/VDD2
CLKOUT
DRAIN2
COMP2
NAME
-40
SYNC
N.C.
EN2
FB2
A
= +25°C, unless otherwise noted.)
OUTPUT LOAD CURRENT LIMIT
-5
vs. TEMPERATURE
OUTPUT1
OUTPUT2
Clock Output. CLKOUT is 45° phase-shifted with respect to converter 2 (SOURCE2, Figure 3). Connect
CLKOUT (master) to the SYNC of a second MAX5073 (slave) for a four-phase converter.
Buck Converter Operation—Bootstrap Flying-Capacitor Connection for Converter 2. Connect BST2/VDD2
to an external ceramic capacitor and diode according to the standard application circuit (Figure 1).
Boost Converter Operation—Driver Bypass Capacitor Connection. Connect a low-ESR 0.1µF ceramic
capacitor from BST2/VDD2 to PGND (Figure 8).
Connection to Converter 2 Internal MOSFET Drain. Buck converter operation—use the MOSFET as a
high-side switch and connect DRAIN2 to the input supply. Boost converter operation—use the MOSFET
as a low-side switch and connect DRAIN2 to the inductor and diode junction (Figure 8).
Acti ve- H i g h E nab l e Inp ut for C onver ter 2. D r i ve E N 2 l ow to shut d ow n conver ter 2, d r i ve E N 2 hi g h for nor m al
op er ati on. U se E N 2 i n conj uncti on w i th E N 1 for sup p l y seq uenci ng . C onnect to V L for al w ays- on op er ati on.
Feed b ack Inp ut for C onver ter 2. C onnect FB2 to a r esi sti ve d i vi d er b etw een conver ter 2’ s outp ut and S GN D
to ad j ust the outp ut vol tag e. To set the outp ut vol tag e b el ow 0.8V , connect FB2 to a r esi sti ve vol tag e- d i vi d er
fr om BY P AS S to r eg ul ator 2’ s outp ut ( Fi g ur e 5) . S ee the S etti ng the O utp ut V ol tag e secti on.
Compensation Connection for Converter 2. See the Compensation section to compensate converter 2’s
control loop.
External Clock Synchronization Input. Connect SYNC to a 400kHz to 4400kHz clock to synchronize the
switching frequency with the system clock. Each converter frequency is one half the frequency applied to
SYNC. Connect SYNC to SGND when not used.
No Connection. Not internally connected.
TEMPERATURE (°C)
30
f
SW
65
V
= 2.2MHz
IN
= 5.5V
Typical Operating Characteristics (continued)
100
FUNCTION
FOUR-PHASE OPERATION
(SEE FIGURE 3)
400ns/div
Pin Description
MAX5073 toc22
SOURCE1
(MASTER)
0V
SOURCE2
(MASTER)
0V
SOURCE1
(SLAVE)
0V
SOURCE2
(SLAVE)