PM6685 STMicroelectronics, PM6685 Datasheet - Page 28

• Manufacturer Part Number: PM6685
• Description: IC CTLR DUAL SYNC STDN 5X5VFQFPN
• Manufacturer: STMicroelectronics

Specifications of PM6685

• Applications: Controller, Notebook Power System
• Voltage - Input: 6 ~ 28 V
• Number Of Outputs: 2
• Voltage - Output: -3.3V, 5V
• Operating Temperature: 0°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-VFQFN, 32-VFQFPN
• Output Voltage: 5 V, 3.3 V
• Output Current: 0.1 A
• Input Voltage: 5.5 V to 28 V
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 10 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Device description
7.11
28/48
●
●
Table 8.
Power up sequencing and operative modes
Let’s consider SHDN, EN5 and EN3 low at the beginning. The battery voltage is applied as
input voltage. The device is in shutdown mode.
When the SHDN pin voltage is above the shutdown device on threshold(1.5V 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 EN5 and EN3 pins are forced high the switching sections begin their soft start
sequence.
LDO3 management is independent from the general power up sequence and depends only
on LDO3_SEL.
Table 9.
LDO3_SEL
Shutdown
VREF
LDO5
GND
Mode
Stand
regulator is turned off and LDO3 output is connected directly to OUT3 pin through an
internal 3 Ω max p-channel MOSFET switch.
If LDO3_SEL is connected to 5V, the internal 3.3 V regulator is always on and supplies
LDO3 output.
If LDO3_SEL is connected to ground, the internal 3.3 V regulator is always off and
LDO3 output is clamped to ground.
Run
LDO3_SEL multifunction pin
Operatives modes
The 3.3V linear regulator is always turned off.
The 3.3V linear regulator is turned off when PGOOD3 is high. LDO3 output is
supplied by the switching 3.3V output.
The 3.3V linear regulator is always turned on and supplies LDO3 output.
SHDN is high EN3/EN5
pins are high
by Both EN5/EN3 pins are
low and SHDN pin is high
SHDN is low
Conditions
Doc ID 11674 Rev 8
Switching regulators are enabled; internal linear
regulators outputs are enabled.
Internal Linear regulators active (LDO5 is always on
while LDO3 depends on LDO3_SEL pin). In Standby
mode LGATE5/LGATE3 pins are forced high while
HGATE5/HGATE3 pins are forced low.
All circuits off.
Description
Description
PM6685