ADP1650CB-EVALZ Analog Devices Inc, ADP1650CB-EVALZ Datasheet - Page 18

• Manufacturer Part Number: ADP1650CB-EVALZ
• Description: LED Flash Driver Eval. Board
• Manufacturer: Analog Devices Inc

Specifications of ADP1650CB-EVALZ

• Core Chip: ADP1650
• Topology: Boost
• Output Current: 1.5A
• No. Of Outputs: 1
• Input Voltage: 2.7V To 5V
• Kit Contents: Board
• Development Tool Type: Hardware - Eval/Demo Board
• Mcu Supported Families: ADP1650
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ADP1650
SAFETY FEATURES
For critical fault conditions, such as output overvoltage, flash
timeout, LED output short circuit, and overtemperature
conditions, the ADP1650 has built-in protection modes. If a
critical fault occurs, OUTPUT_EN (Register 0x04) is set to 0,
and the driver shuts down. The appropriate fault bit is set in the
fault information register (Register 0x05). The processor can
read the fault information register through the I
determine the nature of the fault condition. When the fault
register is read, the corresponding fault bit is cleared.
If a noncritical event such as an indicator LED open/short or a
TxMASK1 or TxMASK2 event occurs, or the dc current limit or
soft inductor current limit is hit, the LED driver continues
operating. The corresponding information bits are set in the
fault information register until the processor reads them.
SHORT-CIRCUIT FAULT
When the flash driver is disabled, the high-side current regulator
disconnects the dc path between the battery and the LED, pro-
tecting the system from an LED short circuit. The LED_OUT
pin features short-circuit protection that monitors the LED
voltage when the LED driver is enabled. If the LED_OUT pin
remains below the short-circuit detection threshold, a short
circuit is detected. Bit 6 of the fault information register is set
high. The ADP1650 remains disabled until the processor clears
the fault register.
OVERVOLTAGE FAULT
The ADP1650 contains a comparator at the VOUT pin that
monitors the voltage between VOUT and GND. If the voltage
exceeds 5.5 V (typical), the ADP1650 shuts down. Bit 7 in the
fault information register is read back as high. The ADP1650 is
disabled until the fault is cleared, ensuring protection against an
open circuit.
DYNAMIC OVERVOLTAGE MODE (DOVP)
Dynamic OVP mode is a programmable feature that limits the
VOUT voltage exceeding the OVP level while maintaining as
much current as possible through the LED. This mode prevents
an overvoltage fault in the case of a much higher than expected
LED forward voltage. If the LED forward voltage reduces due to
the LED temperature rising, the ADP1650 moves out of DOVP
mode and regulates the LED at the programmed current level.
Set Bit 7 of Register 0x07 high to enable dynamic OVP mode.
TIMEOUT FAULT
When external strobe mode is enabled (Register 0x04, Bit 2),
and strobe is set to level-sensitive mode (Register 0x04, Bit 5),
if the strobe pin remains high for longer than the programmed
timeout period, the timeout fault bit (Register 0x05, Bit 4) is
read back as high. The ADP1650 remains disabled until the
processor clears the fault register.
2
C interface to
Rev. C | Page 18 of 32
OVERTEMPERATURE FAULT
If the junction temperature of the ADP1650 rises above 150°C,
a thermal protection circuit shuts down the device. Bit 5 of the
fault information register is set high. The ADP1650 remains
disabled until the processor clears the fault register.
INDICATOR LED FAULT
The GPIO2 pin features open- and short-circuit protection in
the indicator LED mode. If a short or open circuit occurs, Bit 2
of the fault information register is set high. The indicator LED
regulator ensures that no damage occurs to the IC during a fault.
CURRENT LIMIT
The internal switch limits battery current by ensuring that the
peak inductor current does not exceed the programmed limit
(current limit is set by Bit 6 and Bit 7 in Register 0x04). The
default mode of the ADP1650 is soft current limit mode. If the
peak inductor current hits the limit, Bit 1 of the fault informa-
tion register is set, and the inductor and LED current cannot
increase further. The ADP1650 continues to operate. If the
ADP1650 has soft current limit disabled and the peak inductor
current exceeds the limit, the part shuts down and Bit 1 of the
fault information register is set high. In this case, ADP1650
remains disabled until the processor clears the fault register.
INPUT UNDERVOLTAGE
The ADP1650 includes a battery undervoltage lockout circuit.
During 5 V or LED operation, if the battery voltage drops below
the 2.4 V (typical) input UVLO threshold, the ADP1650 shuts
down. A power-on reset circuit resets the registers to their
default conditions when the voltage rises above the UVLO
rising threshold.
SOFT START
The ADP1650 has a soft start mode that controls the rate of
increase of battery current at startup by digitally controlling the
output current ramp. The maximum soft start time is 0.6 ms.
RESET USING THE ENABLE (EN) PIN
A low-to-high transition on the EN pin resets all registers to
their default values. Bringing EN low reduces the I
(typical).
CLEARING FAULTS
The information bits and faults in Register 0x05 clear
automatically when the processor reads the fault register.
Q
to 0.2 μA