Lo w -No is e , 5 .5 V-In p u t ,
P WM S t e p -Do w n Re g u la t o r
MAX1692
ELECTRICAL CHARACTERISTICS (continued)
(V = +3.6V, SYNC/PWM = GND, V
= 3.6V, SHDN = IN, circuit of Figure 2; T = 0°C to +85°C, unless otherwise noted. Typical
IN
LIM
A
values are at T = +25°C.)
A
PARAMETER
Reference Load Regulation
Undervoltage Lockout Threshold
Logic Input High
SYMBOL
CONDITIONS
MIN
TYP
3
MAX
15
UNITS
mV
V
0 ≤ I
≤ 50µA
REF
UVLO
V
IN
rising, typical hysteresis is 85mV
2.3
2
2.4
2.5
V
IH
V
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
High or low
Logic Input Low
V
IL
0.4
1
V
Logic Input Current
-1
0.1
µA
ns
SYNC/PWM Minimum Pulse Width
500
ELECTRICAL CHARACTERISTICS
(V = +3.6V, SYNC/PWM = GND, V
= 3.6V, SHDN = IN, circuit of Figure 2, T = -40°C to +85°C, unless otherwise noted.) (Note 3)
A
IN
LIM
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX
UNITS
Input Voltage Range
Output Voltage
V
2.7
5.5
V
IN
FB = OUT, V = V
= 2.7V to 5.5V,
IN
LIM
1.213
1.285
I
= 0
OUT
V
OUT
V
FB = OUT, V = 2.7V to 5.5V,
IN
I
= 0 to 600mA, LIM = IN or
= 0 to 250mA, LIM = GND
1.185
1.285
OUT
I
OUT
Output Adjustment Range
Feedback Voltage
(Note 1)
FB = OUT, V = V
(duty cycle = 23%) (Note 2)
REF
V
V
V
IN
= 5.5V, I = 0
OUT
IN
LIM
V
FB
1.213
1.285
FB Input Current
I
FB
V
=1.4V
-50
0.3
0.7
50
0.9
1.6
nA
A
FB
LIM = GND
LIM = IN
P-Channel Current-Limit
Threshold
N-Channel Current-Limit
Threshold
SYNC/PWM = IN, FB = REF
-15
110
140
mA
µA
SYNC/PWM = GND, LX = unconnected,
= 1.4V
Quiescent Current
V
FB
Shutdown Supply Current
Oscillator Frequency
10
µA
kHz
V
SHDN = LX = GND, includes LX leakage current
f
630
840
OSC
Reference Output Voltage
V
I
= 0
1.230
1.268
REF
REF
Undervoltage Lockout
Threshold
UVLO
V
rising, typical hysteresis is 85mV
2.3
2
2.5
V
IN
Logic Input High
Logic Input Low
Logic Input Current
V
IH
V
V
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
V
IL
0.4
1
-1
µA
Note 1: Guaranteed by minimum and maximum duty-factor tests.
Note 2: The following equation can be used to calculate FB accuracy for output voltages other than 1.232V:
(see Feedback Voltage vs. Load Current)
V
FB
= V
- (Line Reg) (V
/ V - 0.23) / 0.77 - ( Load Reg )(I
+ 0.5 · I
) / I
FB (NOMINAL)
OUT
IN
OUT
RIPPLE MAX
where: Line Reg = the line regulation
Load Reg = the load regulation
I
= (1- V
/ V ) · V
/ (f
OSC
· L) where L is the inductor value
RIPPLE
OUT
IN
OUT
I
= 250mA (LIM = GND) or 600mA (LIM = IN)
MAX
Note 3: Specifications to -40°C are guaranteed by design, not production tested.
_______________________________________________________________________________________
3
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
