Rainbow Electronics MAX889 - Manual (Page 3)

MAX889
High-Frequency, Regulated,
200mA, Inverting Charge Pump
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Note 1: Specifications to -40 °C are guaranteed by design, not production tested.
ELECTRICAL CHARACTERISTICS
(V IN = V SHDN = +5V, capacitors from Table 1, T A = -40 °C to +85°C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN MAX UNITS
Supply Voltage Range V IN R LOAD = 100 Ω 2.7 5.5 V
Output Voltage Range V OUT R LOAD = 100 Ω -2.5 -V IN V
I OUT(MAX)1 V IN = 5V, V OUT = -3.3V 200
Maximum Output Current
I OUT(MAX)2 V IN = 3.3V, V OUT = -2.5V 145
mA
MAX889R 12
MAX889S 24
Quiescent Supply
Current (Free-Run Mode)
I Q(FREE-RUN) No load, V FB = V IN
MAX889T 48
mA
MAX889R 7
MAX889S 12
Quiescent Supply
Current (Regulated Mode)
I Q(REGULATED)
No load, V OUT regulated to
-3.3V
MAX889T 22
mA
Shutdown Supply Current I SHDN V SHDN = 0 50 µA
Open-Loop Output
Resistance (Free-Run Mode)
R O V FB = V IN 4.5 Ω
SHDN FB Input Bias Current ±1 µA
FB Input Offset Voltage I LOAD = 0 ±35 mV
IN Undervoltage Lockout
Threshold
V IN rising (30mV hysteresis) 2.3 2.6 V
SHDN Logic High V IH 0.7 x V IN
SHDN Logic Low V IL
V IN = +2.7V to +5.5V
0.3 x V IN
V
MAX889R 0.375 0.62
MAX889S 0.75 1.25 Switching Frequency f OSC
MAX889T 1.5 2.5
MHz
Typical Operating Characteristics
(Circuit of Figure 1, V IN = V SHDN = +5V, capacitors from Table 1, T A = +25°C, unless otherwise noted.)
OUTPUT VOLTAGE
vs. LOAD CURRENT
MAX889 toc01
OUTPUT LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
-3.33
-3.32
-3.31
-3.30
-3.29
-3.28
-3.27
-3.26
-3.25
0 200 400 600 800
MAX889T
MAX889S
MAX889R
0
10
20
30
40
MAX889R
OUTPUT RIPPLE
vs. LOAD CURRENT vs. C OUT
MAX889 toc02
LOAD CURRENT (mA)
OUTPUT RIPPLE (mV)
0 150 200 50 100 250 300 350
C OUT = 22 µF
C OUT = 47 µF
C OUT = 10 µF
0
10
20
30
40
MAX889S
OUTPUT RIPPLE
vs. LOAD CURRENT vs. C OUT
MAX889 toc03
LOAD CURRENT (mA)
OUTPUT RIPPLE (mV)
0 150 200 50 100 250 300 350
C OUT = 4.7 µF
C OUT = 22 µF
C OUT = 10 µF