
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only, and functional operation of the
device at these ratings or any other above those indicated in
the operation sections of the specifications below is not
implied. Exposure to absolute maximum rating conditions for
extended periods of time may affect reliability.
Input Voltage….................................................-0.3V to 30V
Lx………………………………………………….…-2V to 30V
FB……………..................................................-0.3V to 5.5V
Storage Temperature..………………...……-65 ° C to 150 ° C
Junction Temperature...................................-40 ° C to 125 ° C
Lead Temperature (Soldering, 10 sec)…..…………..300 ° C
ESD Rating………..….…1kV LX, 2kV all other nodes, HBM
____________________________________________ ELECTRICAL SPECIFICATIONS
Specifications are for T AMB =T J =25 ° C, and those denoted by ? apply over the full operating range, -40 ° C< T j <125 ° C. Unless
otherwise specified: VIN =4.5V to 29V, C IN = 4.7 μ F.
PARAMETER
UVLO Turn-On Threshold
UVLO Turn-Off Threshold
MIN
4.2
4.0
TYP
4.35
4.15
MAX
4.5
4.4
UNITS
V
V
?
CONDITIONS
0 ° C< T j <125 ° C
0 ° C< T j <125 ° C
UVLO Hysteresis
0.2
V
Operating Input Voltage Range
Operating Input Voltage Range
Operating VCC Current
Reference Voltage Accuracy
Reference Voltage Accuracy
4.5
7
0.3
0.5
0.5
29
29
3
1
2
V
V
mA
%
%
?
?
0 ° C< T j <125 ° C
VFB=1.2V
Reference Voltage
0.594
0.6
0.606
V
Reference Voltage
Switching Frequency
0.588
750
0.6
900
0.612
1050
V
kHz
?
Peak-to-peak ramp Voltage
V IN /5
V
Minimum ON-Pulse Duration
40
100
ns
?
Minimum Duty Cycle
Maximum Duty Cycle
100
0
%
%
Gate Driver Turn-Off Resistance
Gate Driver Pull-Down
Resistance
Gate Driver Pull-up Resistance
50
4
3
60
8
6
k
Internal resistor between GATE and
VIN
VIN=12V, V FB =0.5V, Measure
resistance between GATE and VDR
VIN=12V, V FB =0.7V, Measure
resistance between GATE and VIN
VIN - VDR voltage difference
4.5
5.5
V
?
Measure VIN – VDR, VIN>7V
Overcurrent Threshold
LX pin Input Current
270
25
300
30
330
35
mV
uA
Measure VIN - LX
V LX = VIN
OFF interval during hiccup
70
ms
Soft start time
3
5
9
ms
VFB=0.58V, measure between
VIN=4.5V and first GATE pulse
SHDN Threshold
0.8
1.0
1.2
V
?
Apply voltage to FB
SHDN Threshold Hysteresis
100
mV
Jan28-08 RevE
SP6127 TSOT-6 PFET Buck Controller
Page 2
? 2007 Exar Corporation