ADP5050ACPZ-R7 datasheet(26/60 Pages) AD

26 / 60 page

ADP5050

Data Sheet

Rev. 0 | Page 26 of 60

THERMAL SHUTDOWN

If the ADP5050 junction temperature exceeds 150°C, the thermal

shutdown circuit turns off the IC except for the internal linear

regulators. Extreme junction temperatures can be the result of

high current operation, poor circuit board design, or high ambient

temperature. A 15°C hysteresis is included so that the ADP5050

does not return to operation after thermal shutdown until the

on-chip temperature falls below 135°C. When the part exits ther-

mal shutdown, a soft start is initiated for each enabled channel.

The thermal shutdown status can be read via the I2C interface

(Register 12, LCH_STATUS). When thermal shutdown is detected,

the TSD_LCH bit (Bit 4) is set to 1. To clear the status bit, write a

1 to the bit (provided that the fault no longer persists). The status

bit is latched until a 1 is written to the bit or the part is reset by

the internal VDD power-on reset signal.

OVERHEAT DETECTION

In addition to thermal shutdown protection, the ADP5050

provides an overheat warning function, which compares the

junction temperature with the specified overheat threshold:

105°, 115°, or 125°. The overheat threshold is configured in

detection function sends a warning signal but does not shut

down the part. When the junction temperature exceeds the

overheat threshold, the status bit TEMP_INT in Register 14

is set to 1. The status bit is latched until a 1 is written to the bit,

all ENx pins are taken low, or the part is reset by the internal

VDD power-on reset signal.

The overheat detection function can be used to send a warning

signal to the host processor. After the host processor detects the

overheat warning signal, the processor can take action to prepare

for a possible impending thermal shutdown.

Figure 54 shows the overheat warning function.

JUNCTION TEMPERATURE

TIME

TEMP_INT

(HEAT STATUS)

OVERHEAT

CONDITION

DETECTED

NORMAL

TEMPERATURE

115°C

(ADJUSTABLE)

Figure 54. Overheat Warning Function

LOW INPUT VOLTAGE DETECTION

In addition to undervoltage lockout (UVLO), the ADP5050

provides a low input voltage detection circuit to monitor PVIN1;

this circuit compares the input voltage with the specified voltage

threshold. The voltage threshold can be set from 4.2 V to 11.2 V

in steps of 0.5 V using Register 9, TH_CFG. Unlike UVLO shut-

down, the low input voltage detection function sends a warning

signal but does not shut down the part. When the PVIN1 input

voltage falls below the threshold, the status bit LVIN_INT in

to the bit, all ENx pins are taken low, or the part is reset by the

internal VDD power-on reset signal.

The low input voltage detection function can be used to send a

warning signal to the host processor. After the host processor

detects the low input voltage warning signal, the processor can

take action to prepare for a possible impending UVLO shutdown.

Figure 55 shows the low input voltage warning function.

INPUT VOLTAGE ON PVIN1

TIME

LVIN_INT

(LVIN STATUS)

LOW INPUT

VOLTAGE

CONDITION

DETECTED

12V INPUT

VOLTAGE

10.7V

(ADJUSTABLE)

Figure 55. Low Input Voltage Warning Function (VIN = 12 V)

LDO REGULATOR

The ADP5050 integrates a general-purpose LDO regulator with

low quiescent current and low dropout voltage. The LDO regu-

lator provides up to 200 mA of output current.

The LDO regulator operates with an input voltage of 1.7 V to

5.5 V. The wide supply range makes the regulator suitable for

cascading configurations where the LDO supply voltage is

provided from one of the buck regulators. The LDO output

voltage is set using an external resistor divider (see Figure 56).

LDO

FB5

VOUT5

EN5

PVIN5

1µF

1.7V TO 5.5V

Figure 56. 200 mA LDO Regulator

The LDO regulator provides a high power supply rejection ratio

(PSRR), low output noise, and excellent line and load transient

response using small 1 µF ceramic input and output capacitors.

ADP5050ACPZ-R7 数据表(PDF) 26 Page - Analog Devices

ADP5050ACPZ-R7 数据表(HTML) 26 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

数据表下载