PM6680ATR STMicroelectronics, PM6680ATR Datasheet - Page 28

• Manufacturer Part Number: PM6680ATR
• Description: IC CTRLR DUAL STEP DOWN 32VFQFPN
• Manufacturer: STMicroelectronics

Specifications of PM6680ATR

• Applications: Controller, Embedded Computer System
• Voltage - Input: 6 ~ 36 V
• Number Of Outputs: 2
• Voltage - Output: 0.9 ~ 5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 32-VFQFN, 32-VFQFPN
• For Use With: 497-6379 - BOARD EVALUATION FOR PM6680A497-6378 - BOARD EVALUATION FOR PM6680497-6425 - BOARD EVAL BASED ON PM6680A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6896-2; PM6680ATR

Device description
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Power up sequencing and operative modes
Let us consider SHDN, EN1 and EN2 low at the beginning. An external voltage is applied as
input voltage. The device is in shutdown mode.
When the SHDN pin voltage is above the shutdown device on threshold (1.5 V typ.), the
controller begins the power-up sequence. All the latched faults are cleared. LDO5
undervoltage control is blanked for 4 ms and the internal regulator LDO5 turns on. If the
LDO5 output is above the UVLO threshold after this time, the device enters in standby
mode. The switching outputs are kept to ground by turning on the low side MOSFETs.
When EN1 and EN2 pins are forced high the switching sections begin their soft start
sequence.
Table 8.
Shutdown
Standby
Mode
Run
Operatives modes
SHDN is high,
EN1/EN2 pins are high
Both EN1/EN2 pins are low
and SHDN pin is high
SHDN is low
Conditions
Switching regulators are enabled; internal linear
regulators outputs are enabled.
Internal Linear regulators active (LDO5 is always on).
In Standby mode LGATE1/LGATE2 pins are forced
high while HGATE1/HGATE2 pins are forced low.
All circuits off.
Description
PM6680A