Ricoh R1163x - 50 mA LDO with only 1 nA Reverse Current | Ricoh Europe: copiers, photocopiers, printers, gelsprinters, multifunctional printers

Amstelveen, The Netherlands, September, 2004 -- Ricoh Europe B.V., the European headquarters of Ricoh Company Ltd., Tokyo, announces the launch of the R1163x LDO regulator. The Ricoh R1163x features a reverse current protection circuit protecting the P-channel MOSFET of any damage and diminishes leakage current to only 1 nA. In addition, the R1163x can be switched to a low power mode consuming only 6.0 µA. The Ricoh R1163x is available in SOT23-5 and SON6 packages. The combination of these features makes the R1163x an attractive LDO for battery operated applications.

Ricoh's R1163x contains a reverse current protection circuit that prevents a reverse current flowing from V out to the V in terminal and from V out to ground. This problem may occur when an application is operating on a secondary power source such as backup battery or super capacitor connected to the output of the LDO. Ricoh's solution differs from competitor models by completely blocking reverse current flow and reverse current leakage. Reverse current flow is prevented by a P-Channel MOSFET, which is controlled by a patented circuit with a reverse condition detector. An embedded switch prevents reverse current leakage through the feedback resistor array. Therefore the R1163x has a reverse current leakage of only 1 nA, which is far less than that of the closest competitive part in µA order.

When the system requires only a small output current, the R1163x can be switched to low power mode consuming only 6.0 µA, keeping its output voltage. This energy saving mode is especially advantageous to systems that have Off, Stand-by and Normal mode, such as mobile phones. Other products from Ricoh with low power mode are the R1161x and R1162x, with 300 mA and 150 mA output current respectively.

The R1163x works with small ceramic capacitors of minimum 0.47 µF. The designer can choose an output voltage between 1.5 V and 4.0 V in 0.1 V steps. An optional feature in the R1163x is an auto discharge function that rapidly discharges the output capacitor once the chip is in standby mode. The product has a maximum output current of 150 mA.

R1163x Features

Input voltage	2.0 V to 6.0 V
Output voltage	(in 0.1 V steps) 1.5 V to 4.0 V
Accuracy	(I out = 150 mA) Typ. 0.25 V
Reverse current	Typ. 1 nA
Supply current	(ECO pin = Fast transient mode) Typ. 70 µA (ECO pin = Low power mode) Typ. 6.0 µA (CE pin = Stand-by mode) Typ. 0.6 µA
Output current	(Fold back current limit) Typ. 40 mA
Ripple rejection	(ECO pin = Fast transient mode) Typ. 70 dB at f =1 kHz (ECO pin = Fast transient mode) Typ. 60 dB at f =10 kHz (ECO pin = Low power mode) Typ. 35 dB at f =1 kHz
Output capacitors	(Ceramic) Minimum 0.47 µF
Miscellaneous	B version: ECO pin D version: ECO pin and auto discharge function
Packages	SOT23-5 (W 2.8 x L 2.9 x H 1.1 mm) SON6 (W 1.6 x L 3.0 x H 0.85 mm)