Skip to main content Skip to first level navigation

RICOH imagine. change.

RICOH ELECTRONIC DEVICES CO., LTD.

Skip to main content First level navigation Menu
Main content

R1287 Series
PWM/VFM, Dual-channel Step-up/Inverting DCDC Converter with Synchronous Rectifier for LCD

Product Specifications

The R1287 Series are CMOS-based PWM/VFM dual-channel step-up/inverting DC/DC converters with synchronous rectifier for LCD.
The R1287 includes a soft-start circuit, an under-voltage lockout circuit (UVLO), a latch-type short circuit protection, and a thermal shutdown circuit.
By simply using two inductors and three capacitors as external components, a high-efficiency step-up/inverting DC/DC converter can be easily configured.

The R1287 provides two control types: the PWM control and the PWM/VFM auto switching control.
Both CH1 and CH2 can independently control the ON/ OFF control and freely set the starting sequence and shutdown sequence.
Both CH1 and CH2 own an auto-discharge function which actively discharges the output voltage to ground within a short time in shutdown mode.

The R1287 is used for the application of the LCD.

FEATURES

Input Voltage Range (Maximum Rating) 2.5 V ~ 5.5 V (6.0 V)
Supply Current Typ. 470 µA (No switching)
Standby Current Typ. 0.1 µA (EN1 / EN2="L")
Step-up Output Voltage 4.5 V to 5.8 V (internally fixed),
4.5 V to 5.8 V (Externally adjustable, VFBP : 1 V) (001)
Inverting Output Voltage -4.5 V to -5.8 V (internally fixed),
-4.5 V to -6.0 V (Externally adjustable, VFBN : 0 V) (001)
Output Voltage Accuracy (internally fixed) Step-up : ± 0.9%, Inverting : ± 1%
Feedback Voltage Accuracy Step-up : ± 15mV, Inverting : ± 30mV
Output Current Step-up/Inverting: 200 mA (B/D/F/H), 100 mA (C/G)
Oscillator Frequency Step-up: 900 kHz (B/F), 300 kHz (C/G), 1 MHz (D/H)
Inverting: 1.1 MHz (B/F), 300 kHz (C/G), 1 MHz (D/H)
Maximum Duty Cycle Step-up / Inverting: Typ. 90% (B/D/F/H), Typ. 97% (C/G)
UVLO Detect Voltage Typ. 2.25V
Soft Start Time Step-up: Typ. 4.5 ms (C/D/G/H), Max. 5.54 ms (B/F)
Inverting: Typ. 2.6 ms (C/D/G/H), Max. 4.11 ms (B/F)
Coil-current Limit Circuit Step-up: Typ. 1.1 A, Inverting: Typ. 1.5 A
Latch Protection Circuit Delay time for protection Typ. 30 ms
Thermal Shutdown Circuit Stops at 150°C
Function Auto-discharge Function
Package WLCSP-12-P1, DFN3030-12

APPLICATION INFORMATION

Fixed Output Voltage Type

C1(CIN),C2(COUTP),C3(COUTN): 10µF

TYPICAL CHARACTERISTICS

Efficiency vs. Output Current

R1287x001B (Ta=25°C)

R1287x001C (Ta=25°C)

PIN DESCRIPTION

WLCSP-12-P1

WLCSP-12-P11.97 mm × 1.47 mm
A1 VOUTN
A2 PGND
A3 LXP
B1 LXN
B2 GND
B3 VOUTP
C1 PVCC
C2 VCC
C3 VOUTPS (xxxy)
VFBP (001y)
D1 VOUTNS (xxxy)
VFBN (001y)
D2 EN2
D3 EN1

DFN3030-12

DFN3030-123.0 mm × 3.0 mm
1 EN2
2 VOUTNS (xxxy)
VFBN (001y)
3 VCC
4 PVCC
5 LXN
6 VOUTN
7 PGND
8 LXP
9 VOUTP
10 VOUTPS (xxxy)
VFBP (001y)
11 GND
12 EN1

*) The tab is substrate level (GND).


R1287 Series for Consumer

APPLICATIONS

  • Power source for hand-held equipment
  • Power source for LCD

SELECTION GUIDE

The output voltage types are user-selectable options that can be selected from either fixed output voltage type or adjustable output voltage type. With the fixed output voltage type, the combination of a CH1 output voltage and a CH2 output voltage can be selected. The combination of an oscillator frequency, a power controlling method, and a discharge current can also be selected.

Product Name   Package Quantity per Reel
R1287Zxxxy-E2-F Consumter WLCSP-12-P1 4,000
R1287Lxxxy-TR Consumter DFN3030-12 3,000
  • xxx … Specify the set output voltage (VSET).
    001: Adjustable Output Voltage Type, The output voltage is adjustable using external resistors.
    002 to 009: Fixed Output Voltage Type (009 is only available for WLCSP-12-P1 package.)
    CH1 Output Voltage (VOUTP): selectable from +4.5 V to +5.8 V by 0.1 V step (0.05 V step is also available as a custom code.)
    CH2 Output Voltage (VOUTN): selectable from −4.5 V to −5.8 V by 0.1 V step (0.05 V step is also available as a custom code.)
  • y … Specify the oscillator frequency, the power controlling method, and the discharge current.
    B: 1 MHz, PWM/ VFM Auto Switching Control, discharge current 0.06 mA
    C: 300 kHz, Normal PWM Control, discharge current 0.06 mA
    D: 1 MHz, Normal PWM Control, discharge current 0.06 mA
    F: 1 MHz, PWM/ VFM Auto Switching Control, discharge current 0.4 mA
    G: 300 kHz, Normal PWM Control, discharge current 0.4 mA
    H: 1 MHz, Normal PWM Control, discharge current 0.4 mA

DOCUMENT/CONTACT

Purchase

Technical Support

Package *1 Reliability *2
WLCSP-12-P1 R1287Z
DFN3030-12 R1287L

*1: The pwackage file includes package dimensions, taping specifications, taping reels dimensions, and power dissipations.
*2: Reliability file includes a reliability test report and a reflow profile.

Inquiry about products

Technical Support

Inquiries (SSL Form)

Inquiry about business

Purchase, Request for Samples and Documents

Distributors

Sample Online

Online Distributors