L6730C STMicroelectronics, L6730C Datasheet - Page 17

• Manufacturer Part Number: L6730C
• Description: IC CTRLR ADJ STPDN SYNC 20-TSSOP
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L6730C

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: Adj to 0.6V
• Frequency - Switching: 100kHz ~ 1MHz
• Voltage - Input: 1.8 ~ 14 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-TSSOP Exposed Pad, 20-eTSSOP, 20-HTSSOP
• Package: HTSSOP20, QFN4x4 24L
• For Use With: 497-5868 - EVAL BOARD 30A 400KHZ L6730497-5501 - EVAL BOARD FOR L6730XX
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -

L6730C - L6730D
Figure 8.
The reference of the error amplifier is clamped with this voltage (Vss) until it reaches the
programmed value: 0.6V or 1.2V. During the soft-start phase the converter works in closed
loop. The L6730C can only source current during the soft-start phase in order to manage the
prebias start-up applications. The L6730D can always sink current and so it can be used to
supply the DDR Memory termination BUS. If an over current is detected during the soft-start
phase, the device provides a constant-current-protection. In this way, in case of short soft-start
time and/or small inductor value and/or high output capacitors value and thus, in case of high
ripple current during the soft-start, the converter can start-up in any case, limiting the current
(see section 4.5 Monitoring and protections) but not entering in HICCUP mode. The soft-start
phase ends when Vss reaches 3.5V. After that the over-current-protection triggers the HICCUP
mode (L6730C). With the L6730D there is the possibility to set the HICCUP mode or the
constant current mode after the soft-start acting on the multifunction pin CC/O/U. With the
L6730 the low-side MOSFET(s) management after soft-start phase depends on the S/O/U pin
state (see related section). If the sink-mode is enabled the converter can sink current after soft-
start (see figure 9) while, if the sink-mode is disabled the converter never sinks current (see
figure 10)..
Sink-mode enabled: Inductor current during and after soft-start (L6730C).
V
V
V
I
OUT
L
SS
CC
Device description
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