Max781 pda/hand-held computer power controller, Typical operating characteristics (continued) – Rainbow Electronics MAX781 User Manual
Page 6
MAX781
PDA/Hand-Held Computer Power Controller
6
_______________________________________________________________________________________
____________________________Typical Operating Characteristics (continued)
(T
A
= +25°C, unless otherwise noted.)
4
VPPA AND VPPB OUTPUT POWER
VPPA SHORTED TO VPPB AND
CLAMPED TO 11.5V
MAX781-02
BATT VOLTAGE (V)
CURRENT (mA)
VHI VOLTAGE (V)
6
8
10
12
14
16
18
10.5
11.0
11.5
12.0
12.5
13.0
13.5
14.0
50
100
150
200
250
300
350
400
CONFIGURATION = $FF, $00, $02, $6A,
SYNC = AGND, NO 3OUT LOAD
T1 TURNS RATIO (SECONDARY
TURNS / PRIMARY TURNS) = 3.5
VHI VOLTAGE
BATT INPUT CURRENT
VPPA + VPPB CURRENT
10
0
DCHG DUTY CYCLE vs. COMP VOLTAGE
MAX781-04
COMP VOLTAGE (V)
DCHG DUTY CYCLE (%)
20
30
40
50
60
70
80
90
0
0.5
1.0
1.5
2.0
2.5
3.0
AT 0% DUTY CYCLE,
DCHG = 5OUT
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(FIXED 300kHz SWITCHING FREQUENCY)
MAX781-05
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 5.5V
SYNC = REF
IDLE = 0
MODE1 = 1
MODE0 = 0
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(FIXED 230kHz SWITCHING FREQUENCY)
MAX781-06
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 5.5V
SYNC = AGND
IDLE = 0
MODE1 = 1
MODE0 = 0
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(FIXED 300kHz SWITCHING FREQUENCY)
MAX781-08
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 7.5V
SYNC = REF
IDLE = 0
MODE1 = 1
MODE0 = 0
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(VARIABLE SWITCHING FREQUENCY)
MAX781-12
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 5.5V
SYNC = REF
IDLE = 1
MODE1 = 1
MODE0 = 0
0
50
100
150
200
250
300
350
400
450
SWITCHING FREQUENCY (kHz)
%
kHz
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(VARIABLE SWITCHING FREQUENCY)
MAX781-10
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 5.5V
SYNC = AGND
IDLE = 1
MODE1 = 1
MODE0 = 0
0
50
100
150
200
250
300
350
400
450
SWITCHING FREQUENCY (kHz)
%
kHz
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(FIXED 230kHz SWITCHING FREQUENCY)
MAX781-07
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 7.5V
SYNC = AGND
IDLE = 0
MODE1 = 1
MODE0 = 0
10
1
10
100
1000
3OUT OPERATE MODE POWER EFFICIENCY
(VARIABLE SWITCHING FREQUENCY)
MAX781-11
3OUT OUTPUT CURRENT (mA)
POWER EFFICIENCY (%)
20
30
40
50
60
70
80
90
100
BATT = 7.5V
SYNC = REF
IDLE = 1
MODE1 = 1
MODE0 = 0
0
50
100
150
200
250
300
350
400
450
SWITCHING FREQUENCY (kHz)
%
kHz