Inverting dc-dc controllers, Typical operating characteristics – Rainbow Electronics MAX776 User Manual
Page 7

MAX774/MAX775/MAX776
-5V/-12V/-15V or Adjustable,
High-Efficiency, Low I
Q
Inverting DC-DC Controllers
_______________________________________________________________________________________
7
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
CIRCUIT OF FIGURE 2
V+ = 6.5V, I
LOAD
= 1A, V
OUT
= -5V
A: OUTPUT RIPPLE, 200mV/div
B: EXT WAVEFORM, 10V/div
C: INDUCTOR CURRENT, 2A/div
OPERATING WAVEFORMS
10
µ
s/div
A
B
C
CIRCUIT OF FIGURE 2
V
OUT
= -5V, V+ = 4.7V
I
LOAD
= 1.05A (1A/div)
INDUCTOR CURRENT NEAR FULL LOAD
20
µ
s/div
1A/div
0A
CIRCUIT OF FIGURE 2
I
LOAD
= 300mA, V
OUT
= -5V
V+ = 8V, L = 22
µ
H
CONTINUOUS CONDUCTION
AT ONE-HALF CURRENT LIMIT
20
µ
s/div
1A/div
0A
CIRCUIT OF FIGURE 2
V+ = 6V, I
LOAD
= 1A, V
OUT
= -5V
A: SHUTDOWN PULSE, 0V TO V+, 5V/div
B: V
OUT
, 2V/div
ENTRY/EXIT FROM SHUTDOWN
2ms/div
A
B