Rainbow Electronics MAX844 User Manual
Page 9

MAX840/MAX843/MAX844
Low-Noise, Regulated, -2V GaAsFET Bias
_______________________________________________________________________________________
9
MAX840
FB
OUT
SHDN
NEGOUT
C1-
C1+
IN
GND
V
IN
C3
1
µ
F
V
OUT
= -2V
(V
GG
of GaAsFET)
C4
10
µ
F
C1
1
µ
F
C2
1
µ
F
1
ON/OFF
2
3
4
5
6
8
7
MAX840
FB
OUT
SHDN
NEGOUT
C1-
C1+
IN
GND
V
IN
C3
1
µ
F
V
OUT
= (-0.5V) 1+
R2
R1
C4
10
µ
F
C1
1
µ
F
C2
1
µ
F
R2
100k
R1
100k
( )
1
2
3
4
5
6
8
7
ON/OFF
MAX843
MAX844
CONT
OUT
SHDN
NEGOUT
C1-
C1+
IN
GND
V
IN
C3
1
µ
F
V
OUT
= -0.5V to -9.4V @ 4mA
C4
10
µ
F
C1
1
µ
F
C2
1
µ
F
R2
100k
R1
100k
V
CTRL
(0V TO 10V)
1
2
3
4
5
6
8
7
ON/OFF
MAX840
FB
OUT
SHDN
NEGOUT
C1-
C1+
IN
GND
V
IN
C3
0.22
µ
F
V
OUT
= -2V
(V
GG
of GaAsFET)
C4
4.7
µ
F
C1
0.22
µ
F
C2
0.22
µ
F
1
2
3
4
5
6
8
7
ON/OFF
Figure 2a. MAX840 Standard Application Circuit
Figure 2b. MAX840 Adjustable Configuration
Figure 2d. MAX840 Application Circuit Using Smaller Capacitors
Figure 2c. MAX843/MAX844 Standard Application Circuit