Rainbow Electronics MAX1541 - Manual (Page 4)

MAX1540/MAX1541
Dual Step-Down Controllers with Saturation
Protection, Dynamic Output, and Linear Regulator
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, V CC = V DD = ON1 = ON2 = 5V, SKIP = GND, T A = 0°C to +85°C, unless otherwise noted. Typical values are at T A = +25 °C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
FB_ = GND 70 145 350
MAX1540 FB_ = V CC or
adjustable
50 115 220
FB1 = OUT1 400 700 1500
FB2 = GND 90 170 350
OUT_ Input Resistance R OUT _
MAX1541
FB2 = V CC or
adjustable
60 130 270
k Ω
OUT_ Discharge Mode On-
Resistance
R D IS C H ARGE 10 25 Ω
OUT_ Synchronous-Rectifier
Discharge-Mode Turn-On Level
0.2 0.3 0.4 V
Soft-Start Ramp Time t SS Rising edge on ON_ to full current limit 1.7 ms
TON = GN D ( 620kH z) 149 169 190
TON = REF (485kHz) 191 216 242
TON = op en ( 345kH z) 274 304 335
DH1 On-Time t ON1
V+ = 15V,
V
OUT1 = 1.5V
(Note 3)
TON = V CC (235kHz) 402 447 491
ns
TON = GN D ( 460kH z) 201 228 256
TON = REF (355kHz) 260 296 331
TON = op en ( 255kH z) 371 412 453
DH2 On-Time t ON2
V+ = 15V,
V
OUT2 = 1.5V
(Note 3)
TON = V CC (170kHz) 556 618 679
ns
On-Time Tracking t ON2 with respect to t ON1 (Note 3) 120 135 150 %
Minimum Off-Time t OFF(MIN) (Note 3) 400 500 ns
LINEAR REGULATOR (LDO) (Note 1)
0 < I LDOOUT < 10mA 4.85 5.0 5.10 MAX1540 LDO Output-Voltage
Accuracy
V LDOOUT
ON1 = ON2 = GND,
V+ = 6V to 28V
0 < I LD OOU T < 100m A 4.70 5.10
V
0 < I LDOOUT < 10mA 4.85 5.0 5.10
MAX1541 LDO Output-Voltage
Accuracy (Fixed V
LDOOUT )
V LDOOUT
FBLDO = ON1 =
ON2 = GND,
V
LDOIN = 6V to 28V 0 < I LD OOU T < 100m A 4.70 5.10
V
0 < I LDOOUT < 10mA 1.212 1.25 1.275
MAX1541 LDO Feedback
Accuracy (Adjustable V
LDOOUT )
V FBLDO
FBLDO = LDOOUT,
ON1 = ON2 = GND,
V
LDOIN = 4.5V to
28V
0 < I LD OOU T < 100m A 1.175 1.275
V
MAX1541 LDO Output
Adjust Range
1.175 24 V
LDOOUT Short-Circuit Current 130 mA
FBLDO Input Bias Current I FBLDO -0.1 +0.1 µA
MAX1540: V+ - V LDOOUT 500 800
Dropout Voltage
MAX1541: V LDOIN - V LDOOUT 500 800
mV