Typical operating characteristics, Electrical characteristics – Rainbow Electronics MAX1688 User Manual
Page 3
MAX1687/MAX1688
Step-Up DC-DC Converters with
Precise, Adaptive Current Limit for GSM
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS
(V
IN
= V
ON
= +3V, V
LIM
= 1V (MAX1687), V
CHG
= 1V (MAX1688), V
FB
= 1.5V, V
OUT
= 6V,
T
A
= -40°C to +85°C
, unless otherwise noted.)
(Note 1)
Note 1:
Specifications to -40°C are guaranteed by design, not production tested.
V
LIM
= V
CHG
= 1V
V
LIM
= V
CHG
= 0.65V
I
IN
IN rising, 1% hysteresis
V
FB
= 1.125V, V
OUT
= 3V (MAX1688)
FB rising, 2% hysteresis
I
REF
= 0 to 10µA
V
FB
= 1.5V
Shutdown V
IN
= 4.2V, LX2 connected to LX1,
V
OUT
= 0, ON = GND
V
LIM
= V
CHG
= 1V
CONDITIONS
mA
145
240
I
RIPPLE
Ripple Current
A
0.44
0.57
I
PEAK
Ω
0.18
R
SENSE
Sense Resistor
0.73
0.90
Peak Current
V
2.35
2.65
V
2.7
6
Input Voltage Range
Input Undervoltage Lockout
mmho
0.16
0.24
gm
FB
FB Transconductance
V
1.20
1.30
FB Set Voltage
V
1.212
1.288
V
REF
Reference Voltage
ms
0.6
2
T
DELAY
Shutdown Delay
mA
5
I
SHDN
Input Supply Current
µA
10
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
V
IN
= 4V, V
FB
= 0, V
OUT
= 0
V
IN
= 2.7V
V
IN
= 2.7V
Ω
70
Precharge On-Resistance
Ω
0.7
Ω
0.8
N-Channel On-Resistance
P-Channel On-Resistance
Typical Operating Characteristics
(V
IN
= +3.3V, V
OUT
= 5V, V
LIM
= 1V, Figures 6b and 7, T
A
= +25°C, unless otherwise noted.)
60
70
65
80
75
85
95
90
0
150
200
50
100
250
300
350
EFFICIENCY vs. DC LOAD CURRENT
(V
OUT
= 5.5V)
MAX1687/88 toc01
LOAD CURRENT (mA)
EFFICIENCY (%)
V
IN
= 5V
V
IN
= 3.3V
V
IN
= 2.7V
V
IN
= 6V
60
65
70
75
80
85
90
95
0
1500
500
1000
2000
2500
3000
EFFICIENCY vs. GSM BURST LOAD
(V
OUT
= 5.5V)
MAX1687/88 toc02
LOAD CURRENT (mA)
EFFICIENCY (%)
V
IN
= 5V
V
IN
= 3.3V
V
IN
= 2.7V
V
IN
= 6V
60
70
65
80
75
95
90
85
100
0
100
50
150
200
250
300
350
EFFICIENCY vs. LOAD CURRENT
(V
IN
= 2.7V, V
OUT
= 3.3V)
MAX1687/88 toc03
LOAD CURRENT (mA)
EFFICIENCY (%)
V
IN
= 2.7V
V
0.6
V
IL
ON Input Low Voltage
V
V
IN
= 6V
V
IN
= 4.2V
V
IH
ON Input High Voltage
1.8
1.5
V
V
REF
6
Output Voltage Range