Datasheet

MAX764/MAX765/MAX766
-5V/-12V/-15V or Adjustable,
High-Efficiency, Low I
Q
DC-DC Inverters
_______________________________________________________________________________________ 7
CIRCUIT OF FIGURE 2, V+ = 5V, V
OUT
= -5V, I
LOAD
= 80mA
A: OUTPUT RIPPLE, 100mV/div
B: INDUCTOR CURRENT, 500mA/div
C: LX WAVEFORM, 10V/div
5µs/div
DISCONTINUOUS CONDUCTION AT
HALF CURRENT LIMIT
A
B
0A
C
0V
CIRCUIT OF FIGURE 2, V+ = 5V, V
OUT
= -5V, I
LOAD
= 240mA
A: OUTPUT RIPPLE, 100mV/div
B: INDUCTOR CURRENT, 500mA/div
C: LX WAVEFORM, 10V/div
5µs/div
CONTINUOUS CONDUCTION AT
FULL CURRENT LIMIT
A
B
0A
C
0V

______________________________________________________________Pin Description
GroundGND5
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.
V+6, 7
Drain of the Internal P-Channel Power MOSFET. LX has a peak current limit of 0.75A.LX8
1.5V Reference Output that can source 100µA for external loads. Bypass to ground with a 0.1µF capacitor.REF4
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.
SHDN3
PIN
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.
FB2
Sense Input for Fixed-Output Operation (V
FB
= V
REF
). OUT must be connected to V
OUT
.OUT1
FUNCTIONNAME
____________________________Typical Operating Characteristics (continued)
(V+ = 5V, V
OUT
= -5V, T
A
= +25°C, unless otherwise noted.)