Rainbow Electronics MAX8720 - Manual (Page 5)

MAX8720
Dynamically Adjustable 6-Bit VID
Step-Down Controller
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ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, V+ =15V, SHDN = SKIP = V DD = V CC = +5V, V OUT = 1.25V, T A = -40°C to +85°C, unless otherwise noted.
Typical values are at T A = +25°C.) (Note 4)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
PWM CONTROLLER
Battery Voltage, V+ 2 28
Input Voltage Range
V CC , V DD 4.5 5.5
V
DAC codes from 0.9V
to 1.85V
-1 +1 %
DAC codes from
0.45V to 0.875V
-15 +15 DC Output Voltage Accuracy
V+ = 4.5V to 28V,
includes load
regulation error
DAC codes from
0.275V to 0.425V
-18 +18
mV
FB Input Resistance 115 265 k Ω
150kHz, R TIME = 120k Ω -8 +8
818kHz, R TIME = 22k Ω -12 +12 TIME Frequency Accuracy
38kHz, R TIME = 470k Ω -12 +12
%
V+ = 5V, FB = 1.25V, TON = GND
(1000kHz)
230 290
TON = REF
(550kHz)
165 215
TON = open
(300kHz)
320 390
On-Time (Note 2) t ON
V+ = 12V,
FB = 1.25V
TON = V CC
(200kHz)
465 565
ns
TON = V CC , open, or REF (200kHz, 300kHz,
or 550kHz)
500
Minimum Off-Time (Note 2) t OFF(MIN)
TON = GND (1000kHz) 375
ns
BIAS AND REFERENCE
Quiescent Supply Current (V CC ) I CC FB forced above their regulation points 1300 µA
Quiescent Supply Current (V DD ) I DD FB forced above their regulation points 5 µA
Quiescent Battery Supply
Current (V+)
I + 40 µA
Shutdown Supply Current (V CC ) I CC
SHDN = GND 25 µA
Shutdown Supply Current (V DD ) I DD
SHDN = GND 5 µA
Shutdown Battery Supply
Current (V+)
I
+
SHDN = GND, V
CC
= V
DD
= 0V or 5V 5 µA
Reference Voltage V REF V CC = 4.5V to 5.5V, no REF load 1.98 2.02 V
FAULT DETECTION
V
CC
Undervoltage-Lockout
Threshold
Rising edge, hysteresis = 20mV, PWM
disabled below this level
4.1 4.4 V