L6710 STMicroelectronics, L6710 Datasheet - Page 17

• Manufacturer Part Number: L6710
• Description: IC CTRLR 6BIT 2PH PROGR 44-TQFP
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L6710

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 0.84 ~ 1.6 V
• Current - Output: 2A
• Frequency - Switching: 150kHz
• Voltage - Input: 12V
• Operating Temperature: 0°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 44-TQFP, 44-VQFP
• Power - Output: 2.5W
• Product: Half-Bridge Drivers
• Supply Current: 12.5 mA
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 9. OVP (left) and UVP (right) latch.
SOFT START, INHIBIT AND POWER DOWN
At start-up a ramp is generated increasing the loop reference from 0V to the final value programmed by
VID in 2048 clock periods as shown in figure 10.
Once the soft start begins, the reference is increased: upper and lower MOS begin to switch and the output
voltage starts to increase with closed loop regulation. At the end of the digital soft start, the Power Good
comparator is enabled and the PGOOD signal is then driven high (See fig. 10). The Under Voltage com-
parator is enabled when the reference voltage reaches 0.6V. The Soft-Start will not take place, if both VCC
and VCCDR pins are not above their own turn-on thresholds.
During normal operation, if any under-voltage is detected on one of the two supplies the device shuts
down. Forcing the OUTEN pin to a voltage lower than 0.4V (Typ.) disables the device: all the power mos-
fets and protections are turned off until the condition is removed.
Figure 10. Soft Start
V
CC
=V
V
PGOOD
LGATEx
V
CCDR
OUT
Timing Diagram
2048 Clock Cycles
LGATEx
OSC/FAULT
REF_OUT
OUTEN
Turn ON threshold
t
t
t
t
CH1=PGOOD; CH2=REF_OUT;
CH3=VOUT; CH4=LGATEx)
Acquisition:
LGATEx
OSC/FAULT
OUTEN
REF_OUT
L6710
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