MAX1661 Datasheet, PDF (4/16 Pages) Maxim Integrated Products – Active-Matrix Liquid Crystal Display AMLCD Supply

Active-Matrix Liquid Crystal Display
(AMLCD) Supply
__________________________________________Typical Operating Characteristics
(f_BPCLK = 22.5kHz, FPLL = GND, L1 = 3.3µH, L2 = 4.7µH, T_A = +25°C, unless otherwise noted.)
DC-DC 1 EFFICIENCY vs. LOAD CURRENT
(V_OUT1 = +5V)
100
90 V_IN = 3V
80
70
60
V_IN = 4.5V
50
40
30
20
10
0
1
10
100
1000
LOAD CURRENT (mA)
DC-DC 2 EFFICIENCY vs. LOAD CURRENT
(V_OUT2- = -5V)
100
90
V_OUT2+ UNLOADED
80
70
V_IN = 3.3V
60
50
40
V_IN = 5V
30
20
10
0
1
10
100
LOAD CURRENT (mA)
DC-DC 2 EFFICIENCY vs. LOAD CURRENT
(V_OUT2+ = +15V)
100
90
80
V_IN = 5V
70
60
V_IN = 3.3V
50
40
30
20
10
0
1
V_OUT2- UNLOADED
10
100
LOAD CURRENT (mA)
V_OUT1 RIPPLE
10mV/div
500ns/div
I_OUT1 = 250mA, L = 3.3µH
V_OUT2+ RIPPLE
V_OUT2- RIPPLE
V_OUT2
100mV/
div
V_OUT2-
50mV/
div
2µs/div
V_OUT2+ = 15V, V_IN = 3.3V, I_LOAD = 9mA,
C_OUT2 = 0.22µF, AC COUPLED
5µs/div
V_OUT2- = -5V, V_IN = 3.3V, I_LOAD = 5mA,
C_OUT2- = 0.47µF, AC COUPLED
4 _______________________________________________________________________________________