Datasheet

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SLUS564C − JULY 2003 − REVISED OCTOBER 2008
5
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ELECTRICAL CHARACTERISTICS (continued)
T
A
= −40°C to 85°C, 4.5 V < V
IN
< 20 V, C
VIN
= 0.1 µF, C
VREG5
= 2.2 µF, C
REF_X
= 0.01 µF, PGOOD = 0.2 V, ENBLx = DDR = VIN,
INVx = COMPx, RSSTRTx = OPEN, TRIP1 = TRIP2 = VIN, LLx = GND, VBSTx = LLx+5, C
(OUTx_U, OUTx_D)
=1 nF, REG5_IN = 0V, GND =
OUTGNDx = 0 V, VO1_VDDQ = VO2 = 0 V (unless otherwise stated)
PARAMETER UNITMAXTYPMINTEST CONDITIONS
0.85-V REFERENCE CONTROL LOOP
V
REFCH1
Error amplifier reference, channel 1 initial
accuracy
Measure COMP1, COMP1= INV1,
T
A
= 25°C
0.84 0.85 0.86 V
V
REFTC1
Error amplifier reference, channel 1
change with accuracy
0.5%
V
REFLN1
Error amplifier reference, channel 1
change with line
0.1%
V
CHMM
Channel 2 to channel 1 voltage mismatch 0 |5.0| mV
CONTROL LOOP: SKIP HYSTERSTIC COMPARATOR AND ZERO CURRENT COMPARATOR
V
LLHYS
Skip hysteresis comparator hysteresis
(1)
1 2 3
V
LLOFF
Lload hysteresis comparator offset
(1)
0 1
mV
V
ZOFF
Zero current comparator offset
(1)
10 18
mV
T
HLTOLL
PWM skip delay time 8
clks
T
HLTOHL
Skip to PWM delay time 1
clks
CONTROL LOOP ERROR AMPLIFIER
I
EASRC
COMPx source current 0.2 0.9
mA
I
EASNK
COMPx sink current 0.2 0.7
mA
F
UGB
Unity gain bandwidth
(1)
2.5 MHz
A
OL
Open loop gain
(1)
80 dB
CMR
COMP
COMPx voltage range
(1)(6)
0.4 VREG5−3 V
I
INVLEAK
INVx input current |0.5| µA
CONTROL LOOP: DUTY CYCLE, VOLTAGE RAMP, CHANNEL PHASE AND PWM DELAY PATH
f
OSC
= 270 kHz
(3)
86% 88%
DC
MAX
Maximum duty cycle
f
OSC
= 360 kHz
84% 85%
DC
MAX
Maximum duty cycle
f
OSC
= 450 kHz
(2)
80% 82%
PH
CH
Channel to channel phase difference
(5)
PWM phase reversal only 180 °
T
MIN
OUTX_U minimum pulse width
(1)
100 ns
TIMERS: INTERNAL OSCILLATOR
(4)
f
OSC(hi)
Fast oscillator frequency initial accuracy
(2)
R
SSTRTx
= OPEN 450
f
OSC(lo)
Slow oscillator frequency initial accuracy R
SSTRTx
= 1MΩ or V
SSTRT
= 3 V 270
kHz
f
OSC(tc)
Oscillator frequency over line and temperature Trimmed for 360 kHz 306 360 414
kHz
(1)
Ensured by design. Not production tested.
(2)
Maximum 450-kHz frequency can be achieved when both channels are enabled.
(3)
270 kHz is the default frequency during start-up for both channels.
(4)
See Table 1.
(5)
See PWM detailed description