The ADP2450 integrates one boost shunt controller with power
detection, one high efficiency buck regulator, four low offset,
low power consumption programmable gain amplifiers (PGAs),
one low offset operation amplifier, a fast analog trip circuit, and
an actuator driver. The ADP2450 is targeted for low voltage
circuit breakers, such as the molded case circuit breaker
(MCCB), and current transformer (CT) powered supply
applications.
The boost output voltage can be up to 36 V and integrates a
power detection circuit that prevents the circuit from power
hiccups. The power detection threshold is programmable with
resistors.
The buck regulator operates over a wide input voltage range of
4.5 V to 36 V, and the output voltage can be adjusted down to
0.6 V. The buck regulator provides output currents of up to
500 mA. The buck regulator works in pulse-width modulation
(PWM) mode with a fixed 1.2 MHz switching frequency,
providing low output ripple voltage to the system.
The output voltage of the buck regulator is monitored by the
supervisory circuit. When the output voltage is below the
monitoring threshold, 88% of VFB2 (FB2 regulation voltage), the
reset signal is pulled low and can be used to reset the
microprocessor. The monitoring supervisory circuit makes the
system more reliable.
The ADP2450 integrates four low offset, low power consumption
amplifiers. With the programmable gain features, the ADP2450
provides accuracy measurement over a wide current input range
based on the CT turn ratio.
A low offset operation amplifier is integrated in the ADP2450
for leakage current detection.
The ADP2450 also integrates an analog trip circuit, which
provides fast trip response and enhances system reliability.
Additional protection includes buck overcurrent protection
(OCP) and system thermal shutdown (TSD).
The ADP2450 operates over the −40°C to +125°C junction
temperature range and is available either in a 32-lead LFCSP or
a 48-lead LQFP packages.
Applications
- Low voltage circuit breaker
- CT powered supply
