HR1117V-5.0

The HR1117 series are low dropout three-terminal linear regulators with a 1.15V (typical) dropout voltage at 1A output current. They are available in two versions: fixed voltage output and adjustable voltage output. Fixed output voltages are 1.2V, 1.8V, 2.5V, 3.3V, and 5V; the adjustable version requires only two external resistors to provide output voltages from 1.25V to 12V. The output voltage of the adjustable version follows the formula: Vout = 1.25×(1 + R2/R1) + IADJ×R2. Since IADJ (approximately 50μA) is much smaller than the current through R1 (approximately 2~10mA), IADJ can be neglected. To meet the minimum load current requirement (>10mA), R1 is recommended to be 125Ω or lower. Since the HR1117XX-ADJ can maintain stability at a load current of approximately 2mA, R1 must not exceed 625Ω. A bypass capacitor (CADJ) connected between the FB pin and ground can improve ripple rejection. This bypass capacitor prevents ripple amplification as the output voltage increases. The impedance of CADJ should be less than R1 to prevent ripple amplification. Since R1 typically falls in the range of 100Ω~500Ω, the value of CADJ should satisfy the formula: 1 / (2π×fripple×CADJ) < R1.

Applications

• Computer motherboard
• LCD monitor
• Graphics card
• Modem
• Printer

Key features

• Quiescent current: 5mA
• Input voltage range: 15V
• Output current: 1000mA
• Dropout voltage: 1.3V@1A
• Output voltage: 1.25V, 1.8V, 2.5V, 3.3V, 5.0V
• Operating temperature range: -40~85°C