-5 V/-1 2 V/-1 5 V o r Ad ju s t a b le ,
Hig h -Effic ie n c y, Lo w I DC-DC In ve rt e rs
Q
45/MAX76
____________________________Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s (c o n t in u e d )
(V+ = 5V, V
= -5V, T = +25°C, unless otherwise noted.)
A
OUT
DISCONTINUOUS CONDUCTION AT
HALF CURRENT LIMIT
CONTINUOUS CONDUCTION AT
FULL CURRENT LIMIT
A
B
A
B
0A
0V
0A
0V
C
C
5µs/div
5µs/div
CIRCUIT OF FIGURE 2, V+ = 5V, V = -5V, I
= 80mA
CIRCUIT OF FIGURE 2, V+ = 5V, V = -5V, I
= 240mA
OUT
LOAD
OUT
LOAD
A: OUTPUT RIPPLE, 100mV/div
A: OUTPUT RIPPLE, 100mV/div
B: INDUCTOR CURRENT, 500mA/div
C: LX WAVEFORM, 10V/div
B: INDUCTOR CURRENT, 500mA/div
C: LX WAVEFORM, 10V/div
______________________________________________________________P in De s c rip t io n
PIN
NAME
FUNCTION
Sense Input for Fixed-Output Operation (V = V ). OUT must be connected to V
1
OUT
.
OUT
FB
REF
Feedback Input. Connect FB to REF to use the internal voltage divider for a preset output. For adjustable-
output operation, use an external voltage divider, as described in the section Setting the Output Voltage.
2
3
FB
Active-High Shutdown Input. With SHDN high, the part is in shutdown mode and the supply current is less
than 5µA. Connect to ground for normal operation.
SHDN
4
5
REF
1.5V Reference Output that can source 100µA for external loads. Bypass to ground with a 0.1µF capacitor.
Ground
GND
Positive Power-Supply Input. Must be tied together. Place a 0.1µF input bypass capacitor as close to
the V+ and GND pins as possible.
6, 7
8
V+
LX
Drain of the Internal P-Channel Power MOSFET. LX has a peak current limit of 0.75A.
_______________________________________________________________________________________
7
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
