Datasheet


SLUS489 − OCTOBER 2001
5
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electrical characteristics over recommended operating junction temperature range,
T
A
= −40_C to 85_C for the TPS43000, RT = 75 kΩ (500 kHz), VIN = VP = 3.5 V, VOUT = 3.1 V, COMP/FB
pins shorted, BUCK-configured, T
A
= T
J
(unless otherwise noted)
PWM
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
BUCK threshold voltage
BUCK configured if V
BUCK
> 1 V
0.4 0.7 1.0 V
BUCK pull-down current
BUCK configured if V
BUCK
> 1 V
0.5 1.0 µA
BUCK maximum duty cycle V
FB
= 0 V 100%
BOOST maximum duty cycle BUCK grounded, V
FB
= 0 V 70% 90%
Minimum duty cycle V
FB
= 2 V 0%
CCM threshold voltage
Continuous conduction allowed if
0.4 0.7 1.0 V
CCM pull-down current
Continuous conduction allowed if
V
CCM
> 1 V
0.5 1.0 µA
BUCK rectifier zero current threshold voltage Measured from SWP to GND −28 −12 0 mV
BOOST rectifier zero current threshold voltage
Measured from SWP to VOUT,
BUCK grounded
0 14 32 mV
Delay to termination of P-channel gate drive time Measured at PDRV, BUCK grounded 200 300 ns
pulsed frequency modulation
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
PFM threshold voltage
PFM mode not allowed if PFM > 1 V
0.4 0.7 1.0 V
PFM pull-down current
PFM mode not allowed if PFM > 1 V
0.5 1.0 µA
FB voltage to awaken (exit sleep mode) 768 784 800 mV
Izero pulses required to enter sleep 5 7 9
Start-up delay time after sleep 2 5 µs
low power mode
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VOUT threshold voltage to enter low power mode VP = VIN = 5 V 3.45 3.60 3.80
VIN threshold voltage to enter low power mode
VP = VOUT = 5 V,
BUCK grounded (boost configured)
3.45 3.60 3.80
V
Hysteresis voltage to exit low power mode
VOUT < (V
THRESHOLD
−V
HYST
),
VP = VIN = 5 V
225 312 415
Hysteresis voltage to exit low power mode
VIN < (V
THRESHOLD
−V
HYST
),
BUCK grounded, VP = VOUT = 5 V
225 312 415
mV