L6731DTR STMicroelectronics, L6731DTR Datasheet - Page 15

• Manufacturer Part Number: L6731DTR
• Description: IC CTRLR ADJ STPDN SYNC 16-TSSOP
• Manufacturer: STMicroelectronics

Specifications of L6731DTR

• Applications: Controller, DDR
• Voltage - Input: 1.8 ~ 14 V
• Number Of Outputs: 1
• Voltage - Output: Adjustable down to 0.6V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-TSSOP Exposed Pad, 16-eTSSOP, 16-HTSSOP
• Output Voltage: 0.6 V to 18 V
• Input Voltage: 1.8 V to 14 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6112-2

L6731D
5.9
5.10
5.11
Equation 1
During soft-start the OC acts in constant current mode: a current control loop limits the value
of the error amplifier output (comp), in order to avoid its saturation and thus recover faster
when the output returns in regulation.
over current condition that persists also in the soft-start phase.
L6732 provides Under Voltage (UV) protection: when the voltage on FB pin falls below 80%
of the reference, the IC will enter HICCUP mode.
Feedback disconnection is also provided by sourcing a 100 nA current from FB pin. if FB
results being floating, the IC will detect and OV so latching its condition with low side
MOSFET firmly ON.
HICCUP mode during an OCP
Figure 9.
Thermal shutdown
When the junction temperature reaches 150 °C ±10 °C the device enters in thermal
shutdown. Both MOSFETs are turned off and the soft-start capacitor is rapidly discharged
with an internal switch. The device doesn't restart until the junction temperature goes down
to 120 °C and, in any case, until the voltage at the soft-start pin reaches 500 mV.
Minimum on-time (T
The device can manage minimum on-times lower than 100ns. This feature comes down
from the control topology and from the particular over-current-protection system of the
L6731D. In fact, in a voltage mode controller the current has not to be sensed to perform the
regulation and, in the case of L6731D, neither for the over-current protection, given that
Constant current and hiccup mode during an OCP
I
MAX
ON
=
,
I
MIN
VALLEY
Figure 9.
)
+
Vin
shows the behavior of the device during an
−
L
Vout
⋅
T
ON
,
MIN
Device description
VSS
VCOMP
I
L
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