R1204K112A-TR Datasheet: Step-up DC/DC Converter





R1204K112A-TR Step-up DC/DC Converter Datasheet

Part Number R1204K112A-TR
Description Step-up DC/DC Converter
Manufacture RICOH
Total Page 30 Pages
PDF Download Download R1204K112A-TR Datasheet PDF

Features: R1204x Series Step-up DC/DC Converter w ith Shutdown Function No. EA-284-18051 1 OUTLINE The R1204x is a low supply c urrent PWM step-up DC/DC converter. Int ernally, a single IC consists of an NMO S FET, an oscillator, a PWM comparator, a voltage reference unit, an error amp lifier, a current limit circuit, an und er voltage lockout circuit (UVLO), an o ver-voltage protection circuit (OVP), a soft-start circuit, a maximum duty cyc le limit circuit, and a thermal shutdow n protection circuit. By simply using a n inductor, a resistor, capacitors and a diode as external components, a high- efficiency step-up DC/DC converter can be easily configured. As protection fun ctions, the IC contains a thermal shutd own protection circuit, a current limit circuit, an OVP circuit, and an UVLO c ircuit. A thermal shutdown circuit dete cts overheating of the ICs and stops th e operation to protect it from damage. A current limit circuit limits the peak current of Lx, and an OVP circuit detects the over voltage of .

Keywords: R1204K112A-TR, datasheet, pdf, RICOH, Step-up, DC/DC, Converter, stock, pinout, distributor, price, schematic, inventory, databook, Electronic, Components, Parameters, parts, cross reference, chip, Semiconductor, circuit, Electric, manual, substitute, Equivalent

R1204x Series
Step-up DC/DC Converter with Shutdown Function
No. EA-284-180511
OUTLINE
The R1204x is a low supply current PWM step-up DC/DC converter. Internally, a single IC consists of an NMOS
FET, an oscillator, a PWM comparator, a voltage reference unit, an error amplifier, a current limit circuit, an
under voltage lockout circuit (UVLO), an over-voltage protection circuit (OVP), a soft-start circuit, a maximum
duty cycle limit circuit, and a thermal shutdown protection circuit. By simply using an inductor, a resistor,
capacitors and a diode as external components, a high-efficiency step-up DC/DC converter can be easily
configured. As protection functions, the IC contains a thermal shutdown protection circuit, a current limit circuit,
an OVP circuit, and an UVLO circuit. A thermal shutdown circuit detects overheating of the ICs and stops the
operation to protect it from damage. A current limit circuit limits the peak current of Lx, and an OVP circuit
detects the over voltage of output, and an UVLO circuit detects the low input voltage.
The R1204x provides the R1204xxxA/D/G/H versions, which are optimized for serial driving of white LEDs with
constant current, and the R1204xxxB/C/E/F versions, which are optimized for constant voltage driving. Among
the R1204xxxB/C/E/F versions, only the R1204xxxC/F versions are equipped with PWM/VFM auto-switching
controls. The LED current can be determined by the value of current setting resistor. The brightness of the
LEDs can be quickly adjusted by applying a PWM signal (200 Hz to 300 kHz) to the CE pin. The R1204x is
available in DFN(PLP)1820-6 and TSOT-23-6 packages.
FEATURES
Input Voltage Range..........................................2.3 V to 5.5 V
Supply Current ..................................................Typ. 800 µA
Standby Current ................................................Max. 5 µA
Feedback Voltage .............................................0.2 V ±10 mV (R1204xxxxA/D)
0.4 V ±10 mV (R1204xxxxG/H)
V ±15 mV (R1204xxxxB/C/E/F)
Lx Current Limit Function..................................Min. 700 mA
Over Voltage Protection ....................................23 V, 33 V, 42 V (±1.5 V)
Oscillator Frequency .........................................Typ. 1.0 MHz (R1204xxxxA/B/C/G)
Typ. 750 kHz (R1204xxxxD/E/F/H)
Maximum Duty Cycle ........................................Min. 91% (R1204xxxxA/B/C/G)
Min. 92% (R1204xxxxD/E/F/H)
FET ON Resistance ..........................................Typ. 0.8
UVLO Function
Thermal Protection Function
LED Dimming Control for R1204xxxxA/D .........by external PWM signal (200 Hz to 300 kHz frequency)
Packages ..........................................................DFN(PLP)1820-6, TSOT-23-6
Recommended Bypass Capacitor ....................1.0 µF
APPLICATIONS
Constant voltage power source for hand-held equipment
OLED power supply for hand-held equipment
White LED driver for hand-held equipment
1

                    
                    






Index : 0  1  2  3   4  5  6  7   8  9  A  B   C  D  E  F   G  H  I  J   K  L  M  N   O  P  Q  R   S  T  U  V   W  X  Y  Z
@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)