Datasheet

Output
Voltage
time
V
OUT,A
V
OUT,B
Δt
ΔV
OUT
10 mV
10 mV/Ramp Rate
Output
Voltage
time
V
OUT,A
V
OUT,B
Δt
ΔV
OUT
20 mV
20 mV/Ramp Rate
(TPS62360 / TPS62362)
(TPS62361B / TPS62363)
Output
Voltage
time
V
OUT,A
V
OUT,B
Δt
ΔV
OUT
10 mV
10 mV/Ramp Rate
(TPS62360 / TPS62362)
Output
Voltage
time
V
OUT,A
V
OUT,B
Δt
ΔV
OUT
20 mV
20 mV/Ramp Rate
(TPS62361B / TPS62363)
TPS62360, TPS62361B
TPS62362, TPS62363
www.ti.com SLVSAU9C –MAY 2011–REVISED NOVEMBER 2012
If the RAMP_PFM bit is not set in Power Save Mode, the slope can be less at low output currents since the
device does not actively source energy back from the output capacitor to the input or it might be sharper at high
output currents since the output capacitor is discharged quickly.
Figure 38. Ramp Up
Figure 39. Ramp Down
The TPS62360 and TPS62362 ramp the output voltage taking 10mV steps, while the TPS62361B and
TPS62363 ramp taking 20mV steps with a final 10mV step if required. The resulting slope remains equal for both
devices.
While the output voltage setpoint is changed in a digital stair step fashion, the connected output capacitor flattens
the steps to create a linear change in the output voltage.
SAFE OPERATION AND PROTECTION FEATURES
Inductor Current Limit
The inductor current limiting prevents the device from drawing high inductor current and excessive current from
the battery. Excessive current might occur with a shorted/saturated inductor or a heavy load/shorted output
circuit condition.
The incorporated inductor peak current limit measures the current while the high side power MOSFET is turned
on. Once the current limit is tripped, the high side MOSFET is turned off and the low side MOSFET is turned on
to ramp down the inductor current. This prevents high currents to be drawn from the battery.
Once the low side MOSFET is on, the low side forward current limit keeps the low side MOSFET on until the
current through it decreases below the low side forward current limit threshold.
The negative current limit acts if current is flowing back to the battery from the output. It works differently in PWM
and PFM operation. In PWM operation, the negative current limit prevents excessive current from flowing back
through the inductor to the battery, preventing abnormal voltage conditions at the switching node. In PFM
operation, a zero current limits any power flow back to the battery by preventing negative inductor current.
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Product Folder Links: TPS62360 TPS62361B TPS62362 TPS62363