ADP2370ACPZ-R7

The ADP2370/ADP2371 are high-efficiency, low quiescent current, 800 mA step-down DC-DC converters in a compact 8-lead, 3 mm×3 mm LFCSP (QFN) package. The complete solution requires only three small external components. The step-down regulator employs a proprietary high-speed current mode, constant-frequency PWM control scheme, delivering excellent stability and transient response. The integrated high-efficiency synchronous rectifier topology eliminates the need for an external rectifier. To maximize battery life in portable applications, the ADP2370/ADP2371 feature a variable-frequency power save mode that reduces switching frequency under light load conditions. These devices operate from a 3.2 V to 15 V input voltage, supporting multiple alkaline/NiMH cells, lithium batteries, or other standard power sources. The ADP2370/ADP2371 offer multiple options for setting the operating frequency. These devices can be synchronized to an external clock at frequencies from 600 kHz to 1.2 MHz, or forced to operate at 600 kHz or 1.2 MHz via the FSEL pin. When noise is a greater concern than efficiency, the ADP2370/ADP2371 can be forced into PWM mode (FPWM) operation. These devices provide a power-good output to indicate when the output voltage falls below 92% of its nominal value. The ADP2371 differs from the ADP2370 in that the ADP2371 includes an additional integrated switching resistor with a quick output discharge (QOD) function, which automatically discharges the output when the device is disabled. To minimize external component count and maximize efficiency, both devices integrate the power switch and synchronous rectifier on-chip. For ease of use, the ADP2370/ADP2371 also include internal soft-start and internal compensation. During logic-controlled shutdown, the input is disconnected from the output, and the current drawn by the regulator from the input source is less than 1.2 μA. Other key features include: undervoltage lockout to prevent deep battery discharge, and soft-start to prevent input overcurrent at startup. Short-circuit protection and thermal overload protection circuits guard against device damage under adverse conditions. Each ADP2370/ADP2371 uses one 0805 capacitor, one 1206 capacitor, and one 4 mm×4 mm inductor. The total solution size is extremely compact, approximately 53 mm², making it suitable for a wide range of portable applications.

Applications

• Portable and battery-powered devices
• Automatic meter reading devices (WSN)
• POS and transaction processing devices
• Medical instruments
• Mid-size tablet PCs

Key features

• Input voltage range: 3.2 V to 15 V, output current: 800 mA
• Quiescent current < 14 μA in PSM
• Efficiency: >90%
• Force PWM pin (SYNC), 600 kHz/1.2 MHz frequency pin (FSEL)
• Fixed output: 0.8 V, 1.2 V, 1.5 V, 1.8 V, 2.5 V, 3.0 V, 3.3 V, 5 V, and adjustable options
• Duty cycle capability: 700%
• Initial accuracy: ±1%
• Low shutdown current: <1.2 μA
• Quick output discharge (QOD) option
• Synchronizable to external clock
• 8-lead, 3 mm×3 mm LFCSP (QFN)
• ADIsimPower design tool support