Datasheet

LT1946A
10
sn1946a 1946afs
Low Profile (<1.1mm Tall) Triple Output TFT Supply (10V, –10V, 20V)
V
IN
V
IN
5V
SW
FB
3
8
7
1
4
2
65
LT1946A
L1
1.5µH
D1
R2
10.5k
R1
75k
R
C
59k
1946A TA02
C2
20µF
C5
0.1µF
C3
1µF
C4
2.2µF
C1
4.7µF
C
C
150pF
C
SS
100nF
D4
V
OFF
–10V
10mA
A
VDD
10V
475mA
V
ON
20V
5mA
D5
C6
0.1µF
V
C
GND*
SHDN
SS
COMP
C1–C6: X5R or X7R
C1: 4.7µF, 6.3V
C2: 2× 10µF, 10V
C3: 1µF, 25V
C4: 2.2µF, 10V
C5–C6: 0.1µF, 10V
D1: MICROSEMI UPS120 OR EQUIVALENT
D2–D5: ZETEX BAT54S OR EQUIVALENT
L1: COILCRAFT LP01704-152MC
* EXPOSED PAD MUST ALSO BE GROUNDED
+
D2 D3
OFF ON
A
VDD
LOAD CURRENT (mA)
EFFICIENCY (%)
1946A TA04
90
85
80
75
70
65
60
55
50
0 100 200 300 400 500
V
ON
LOAD = 5mA
V
OFF
LOAD = 10mA
Transient Response
100µs/DIV 1946A TA03
A
VDD
50mV/DIV
AC COUPLED
I
LI
0.5A/DIV
350mA
200mA
A
VDD
LOAD
Efficiency
TYPICAL APPLICATIO S
U