28V, Low-Power, High-Voltage,
Boost or Inverting DC-DC Converter
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V, C
REF
= 0.1µF, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
REF Load Regulation
Line Regulation
Load Regulation
Thermal Shutdown Threshold
CONDITIONS
I
REF
= 0µA to 100µA, C
REF
= 0.47µF (Note 3)
Circuit of Figure 2, V
OUT
= 24V, V
CC
= 3V to 5.5V,
I
LOAD
= 5mA
Circuit of Figure 2, V
OUT
= 24V, V
CC
= 5V,
I
LOAD
= 0mA to 5mA
Die temperature
MIN
TYP
10
0.2
0.15
150
MAX
25
UNITS
mV
%/V
%
°C
MAX629
Note 1:
Specifications to -40°C are guaranteed by design and not production tested.
Note 2:
The IC itself requires a supply voltage between +2.7V and +5.5V; however, the voltage that supplies power to the inductor
can vary from 0.8V to 28V, depending on circuit operating conditions.
Note 3:
For reference currents less than 10µA, a 0.1µF reference-bypass capacitor is adequate.
__________________________________________Typical Operating Characteristics
(SHDN = V
CC
, C
REF
= 0.1µF, T
A
= +25°C, unless otherwise noted.)
EFFICIENCY vs. LOAD CURRENT
(V
OUT
= +24V)
MAX629-01
EFFICIENCY vs. LOAD CURRENT
(V
OUT
= +12V)
MAX629-02
MAXIMUM LOAD CURRENT vs.
INPUT VOLTAGE (V
OUT
= +24V, +12V)
A: V
OUT
= 12V,
ISET = V
CC
B: V
OUT
= 12V,
ISET = GND
C: V
OUT
=24V,
ISET = V
CC
D: V
OUT
= 24V,
ISET = GND
A
MAX629-03
100
95
90
EFFICIENCY (%)
85
80
75
70
65
60
0.1
1
10
D
E, F
D: V
IN
= 5V, ISET = GND
E: V
IN
= 3V, ISET = V
CC
F: V
IN
= 3V, ISET = GND
V
OUT
= 24V
A: V
IN
= 12V, ISET = V
CC
B: V
IN
= 12V, ISET = GND
C: V
IN
= 5V, ISET = V
CC
C
100
95
A
EFFICIENCY (%)
90
B
85
80
75
70
65
60
C
300
250
200
150
100
D
50
0
A
B
MAXIMUM LOAD CURRENT (mA)
C
B
V
OUT
= 12V,
ISET = V
CC
or GND
A: V
IN
= 9V
B: V
IN
= 5V
C: V
IN
= 3V
0.1
1
10
100
100
0
4
8
12
16
20
LOAD CURRENT (mA)
LOAD CURRENT (mA)
INPUT VOLTAGE (V)
EFFICIENCY vs. LOAD CURRENT
(V
OUT
= -18V)
MAX629-04
EFFICIENCY vs. LOAD CURRENT
(V
OUT
= -12V)
MAX629-05
MAXIMUM LOAD CURRENT vs. INPUT VOLTAGE
(V
OUT
= -18V, -12V)
80
MAXIMUM LOAD CURRENT (mA)
70
60
50
40
30
20
10
0
100
0
4
8
12
16
20
INPUT VOLTAGE (V)
D
C
B
A: V
OUT
= -12V, ISET = V
CC
B: V
OUT
= -18V, ISET = V
CC
C: V
OUT
= -12V, ISET = GND
D: V
OUT
= -18V, ISET = GND
A
MAX629-06
100
95
90
EFFICIENCY (%)
100
95
90
EFFICIENCY (%)
90
85
80
75
70
65
60
55
50
0.1
1
10
A: V
IN
= 12V, ISET = V
CC
B: V
IN
= 12V, ISET = GND
C: V
IN
= 5V, ISET = V
CC
or GND
D: V
IN
= 3V, ISET = V
CC
or GND
D
B
C
A
85
80
75
70
65
60
55
50
A
B, C
D
A = V
IN
= 5V, ISET = V
CC
B = V
IN
= 5V, ISET = GND
C = V
IN
= 3V, ISET = V
CC
D = V
IN
= 3V, ISET = GND
0.1
1
10
100
LOAD CURRENT (mA)
LOAD CURRENT (mA)
_______________________________________________________________________________________
3
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
