RICOH Manuals

R1204x Series PWM/VFM step-up DC/DC converters are optimized to drive white LEDs and OLED with constant current

The R1202x Series are CMOS-based PWM step-up DC/DC converters, which are optimized to drive white LEDs and OLED with constant current. There are two types. The A/B versions are optimized for the general use or the drive of PMOLED, and the D version is optimized for the serial drive of white LED with constant current. The R1202x includes an under-voltage lockout circuit (UVLO), a soft-start circuit, and an over-voltage protection circuit (OVP), a thermal shutdown circuit. By simply using an inductor, divider resisters, and capacitors as external components, OLED and white LEDs can be driven with high efficiently. At the standby mode, the internal NPN transistor can separate the output from the input. (Shutdown function) The A/B version with auto-discharge function is selectable. D Version can set white LED current with feedback resister (R1). The brightness of the LEDs and the soft-start time can be adjusted by applying a PWM signal (200Hz to 300kHz) to the CE pin. In addition to DFN1616-6B, 0.95mm thickness TSOT-23-6 is available.

R1200x series are CMOS-based control type step-up DC/DC converter with low supply current ICs

The R1200x Series PWM Step-up DC/DC converters are CMOS-based PWM step-up DC/DC converters, which are optimized to drive passive matrix OLED or white LEDs with constant current. The R1200x includes an under-voltage lockout circuit (UVLO), a soft-start circuit, and an over-voltage protection circuit (OVP). By simply using an inductor, divider resisters, and capacitors as external components, OLEDs and white LEDs can be driven with high efficiently. At the standby mode, the internal NPN transistor can separate the output from the input. By this shutdown function, white LED's current can be completely shutdown, and output voltage for OLED can be completely cut off, therefore, the R1200x does not have bad impact on the life expectancy of OLED. The version with auto-discharge function is available.

R5533V is a standard type PCMCIA power controller, which has low ON resistance Nch MOSFET switch, built-in over current limit protection function, built-in thermal shutdown protection, open drain flag pin, break-before-make switching and SSOP-16 pin package, which can be applied to PC card power switch, card slot power control and PC card reader / writer, etc.

The R5540 series are N-channel Load Switch ICs with the low supply current, Typ. 9µA. By using an Nch transistor as a driver transistor, the features of low on resistance and the reverse current protection at off state are realized in these ICs. The gate voltage of the N-channel transistor is supplied from the internal step-up circuit. The R5540 is an ideal switch to supply the power from the secondary power source such as the output of a step-down DC/DC to the load circuit. Since the package for the R5540 is the ultra small-sized DFN(PLP)1010-4F, high density mounting on board is possible.

The R5524N series is CMOS-based high-side MOSFET switch ICs for Universal Serial Bus (USB) applications. Using Nch FET as a switching transistor, low ON resistance (Typ.100mΩ) and reverse current protection is possible. An Over-current limit circuit, a thermal shutdown circuit, and an under voltage lockout circuit (UVLO) are built in as protection circuits. Further, a delay circuit for flag signal after detecting over-current, is embedded to prevent miss-operation of error flag because of inrush current. In order to support easy power-line design, the over-current level is highly accurate. The R5524N series is ideal for applications of protection for USB power supply. Since the package is small SOT-23-5, high density mounting on board is possible.

The R5524N series USB high side switch IC is a CMOS-based USB high side switch IC. The R5524N is a protection IC used in the power line of USB with built-in current limit circuit, thermal shutdown circuit, and under-voltage lockout circuit (UVLO). The R5524N001 has the built-in latch-off type over-current limit circuit. When the over-current is detected, the protection circuit becomes active and the switch-transistor is turned OFF. The R5524N002 has the built-in over current protection circuit as the constant current type. It detects as the over-current condition, if the current flows as the ITH defined. Then operating the switch transistor to limit the output current to be the constant current defined by the ILIM. The SOT-23-5 package is available, which is smaller than SOT-89-5 (R5520H).

R5523N Series USB high-side switch IC is a CMOS-based USB high side switch IC with built-in current limit circuit, thermal shutdown circuit, and under-voltage lockout circuit (UVLO).

The R5520H series USB high-side power switch is a CMOS-based high-side MOSFET switch IC for Universal Serial Bus (USB) applications. Low ON Resistance (Typ.100mΩ) and low supply current (Typ.20μA at active mode) are realized in this IC. An over-current limit circuit, thermal shutdown circuit, and an under voltage lockout circuit are built-in as protection circuits. Further, a delay circuit for flag signal after detecting over-current, is embedded to prevent miss-operation of error flag because of inrush current. The R5520H is ideal for applications of protection for USB power supply.

The R5520H series are CMOS-based USB high side switch IC. R5520H is a protection IC used in power line of USB with built-in current limit circuit, thermal shutdown circuit, and under-voltage lockout circuit (UVLO). R5520H contains an internal delay circuit to prevent output of flag signal of false detection caused by inrush current.

The R3200x Series are reset timer ICs with two input signals for mobile equipments which require long interval for reset sequence. The long interval prevents unexpected resets caused by accidental key operations. Internally, each of these ICs consist of a delay generator circuit and output driver transistors. The R3200x Series have two active-low input pins (SR0 and SR1) which generate reset signals after output delay time when both input pins are activated at the same time. R3200x Series has two versions that are different in output delay time settings and output release method. - R3200x001x : Output delay time selectable (7.5s or 11.25s) by connecting DSR pin to either GND or VDD. The reset signal will be canceled if either of the input pin becomes “H”. Until either input pin becomes “H”, the reset signal will be continually outputted. - R3200x002x : Output delay time is fixed at 7.5s. After the reset signal is being output 0.234s, it will be released automatically or if either of the input pin becomes “H”, the reset signal will be canceled. While the reset signals are remaining active or being sent out, the ICs provide ultra-low supply current. The R3200x Series are available in DFN(PLP)2020-8B and DFN1216-8 packages.

R3200x Series are reset timer ICs with two input signals for mobile equipments which require long interval.