LP8720TLX-B/NOPB National Semiconductor, LP8720TLX-B/NOPB Datasheet - Page 4

• Manufacturer Part Number: LP8720TLX-B/NOPB
• Description: IC REG BUCK 5-LDO I2C 20USMD
• Manufacturer: National Semiconductor

Specifications of LP8720TLX-B/NOPB

• Topology: Step-Down (Buck) Synchronous (1), Linear (LDO) (5)
• Function: Any Function
• Number Of Outputs: 6
• Frequency - Switching: 2MHz
• Voltage/current - Output 1: 0.8 V ~ 2.3 V, 400mA
• Voltage/current - Output 2: 1.2 V ~ 3.3 V, 300mA
• Voltage/current - Output 3: 1.2 V ~ 3.3 V, 300mA
• W/led Driver: No
• W/supervisor: No
• W/sequencer: Yes
• Voltage - Supply: 2.7 V ~ 4.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-UFBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Device Description
OPERATION MODES
POWER-ON-RESET: After VBATT gets above POR higher threshold DEFSEL-pin and IDSEL-pin are read. Then all internal
STANDBY:
START UP:
IDLE:
SHUT DOWN:
Additional Functions
SLEEP:
DVS:
INTERRUPT: If interrupt is not masked then PMU forces IRQ_N low if temperature crossed TSD_EW limit (thermal shutdown
If sum of all LDO’s load currents and BUCK load current is no higher than 5mA then user can put PMU to SLEEP.
In SLEEP PMU GND current is minimized. In SLEEP LDO’s and BUCK cannot be loaded with big current.
There are 2 possibilities to use SLEEP:
1) Control via Serial Interface.
2) Control by DVS-pin.
Dynamic Voltage Scaling allows using 2 voltage sets for BUCK. There are 2 possibilities to use DVS:
1) Control via Serial Interface.
2) Control by DVS-pin.
early warning) or/and thermal shutdown event took place. IRQ_N is released by reading Interrupt register.
registers of LP8720 are reset to the default values and after that LP8720 goes to STANDBY mode. This
process duration max is 500 µs.
In STANDBY mode only serial interface is working and all other PMU functions are disabled – PMU is in
low power condition. In STANDBY mode LP8720 can be (re)configured via Serial Interface.
START UP sequence is defined by registers contents. START UP sequence starts:
1) If rising edge on EN-pin.
2) After cooling down from thermal shutdown event if EN=HI.
It is not recommended to write to LP8720 registers during START UP. If doing so then current START UP
sequence may become undefined.
PMU will enter into IDLE mode (normal operating mode) after end of START UP sequence. In IDLE mode
all LDO’s and BUCK can be enabled/disabled via Serial Interface. Also in IDLE mode LP8720 can be (re)
configured via Serial Interface.
SHUT DOWN sequence is “reverse order of start up sequence” and this is defined by registers contents.
SHUT DOWN starts
1) If falling edge on EN-pin.
2) If temperature exceeds thermal shutdown threshold TSD +160°C.
It is not recommended to write to LP8720 registers during SHUT DOWN. If doing so then current SHUT
DOWN sequence may become undefined.
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