Item specifics
Description
RK805-2 is a highly integrated power management IC from Rockchip designed for portable systems. The chip integrates 4 high efficiency DCDC buck converters and 3 high performance LDOs with I2C programmable output voltage and power sequencing control. Input voltage range from 2.7V to 5.5V with 2MHz switching frequency using current mode architecture featuring internal compensation and soft start circuits. Each DCDC and LDO integrates Vout discharge circuit supporting flexible power sequence configuration. Package is 4 by 4 millimeter QFN-32 with 0.4 millimeter pin pitch. Ideal for Rockchip processor companion power, tablets, car infotainment systems, industrial control equipment and smart home terminals for portable and battery powered applications.
RK805-2 Core Features
Power Architecture： 4 DCDC buck converters plus 3 high performance LDO linear regulators
Input Voltage： 2.7V to 5.5V wide input range for single cell lithium battery and USB power
Switching Frequency： 2MHz fixed switching frequency for small external inductor and capacitor
Control Architecture： Current mode PWM control for optimized transient response performance
I2C Interface： Programmable output voltage adjustment and flexible power sequencing configuration
Soft Start： Built in soft start circuit reduces inrush current during power up
Discharge Circuit： Each DCDC and LDO integrates Vout discharge circuit ensuring complete shutdown
Package Type： QFN-32 4 by 4 millimeters with 0.4 millimeter pin pitch
Temperature Range： Industrial grade minus 40 degrees Celsius to 85 degrees Celsius
RK805-2 Applications
Rockchip Processor Companion Power： Complete power solution for Rockchip RK series processors
Tablets： Power management for ARM architecture tablet main processors
Car Infotainment Systems： Wide voltage input and industrial temperature range for automotive applications
Industrial Control Equipment： High reliability design for industrial environments and automation equipment
Smart Home Terminals： Stable power supply for smart speakers and control panels
Portable Electronic Devices： Low power high efficiency design extends battery life
RK805-2 Key Advantages
High Integration Single Chip Solution： 4 DCDC plus 3 LDO replaces multiple discrete power ICs significantly reducing PCB area and BOM cost
I2C Programmability： Dynamic adjustment of output voltage and power sequencing via I2C bus eliminates hardware modifications for different platform requirements
2MHz High Frequency Design： High switching frequency allows smaller inductors and capacitors saving board space for compact product designs
Current Mode Fast Response： Current mode PWM control delivers excellent load transient response ensuring stable processor core voltage
Complete Power Sequencing Control： Programmable power sequencing meets strict power up sequence requirements of processors improving system reliability
Soft Start No Overshoot： Integrated soft start suppresses inrush current protecting downstream loads
Industrial Grade Reliability： Minus 40 to 85 degrees Celsius wide temperature operation for industrial and automotive environments
Why Choose QIXINWEI
Years of experience in the electronics industry. Trusted by global customers.
Massive In-Stock Inventory – Ready to ship promptly
BOM Matching Service – One-stop solution, save time
PCBA Customization – Professional engineering team creates tailor-made solutions based on your needs
Cost-Effective & Efficient – Better channel, better cost
A dedicated team makes your procurement smoother.
Contact us for BOM quotes or PCBA inquiries
FAQ:
What is the Rockchip RK805-2 PMIC and its key specifications?
The RK805‑2 is a highly integrated Power Management IC (PMIC) from Rockchip, designed for cost‑sensitive portable and industrial embedded systems. It combines 4 synchronous step‑down DC‑DC converters (bucks), 2 low‑noise low‑dropout linear regulators (LDOs), an always‑on RTC LDO, a complete single‑cell Li‑Ion battery charger (up to 2 A), a fuel gauge, and an RTC. The device is controlled via I2C (default address 0x18) and comes in a very small QFN‑32 package (5 mm × 5 mm). Its input voltage range is 2.7 V – 5.5 V. It does not include an audio codec, making it a compact, cost‑effective power and charging solution for Rockchip SoCs that handle audio externally or do not require on‑chip sound.
How does the RK805-2 differ from the RK808 or RK809 PMICs?
The RK805‑2 is a more compact and cost‑optimised alternative to the RK808/RK809 families. The RK808 offers 4 bucks and 8 LDOs in a larger QFN‑68 package, while the RK809 adds an integrated audio codec. In contrast, the RK805‑2 provides only 2 LDOs (plus a dedicated RTC LDO) in a tiny QFN‑32 (5×5 mm) package, and uses a different I2C address (0x18 vs 0x1B for RK808 and 0x1A for RK809). It is the ideal choice when board space is extremely tight, the system does not need an audio codec, and only a few clean auxiliary power rails are required alongside the main buck converters and battery charger.
What are the output capabilities of the four DC‑DC buck converters in the RK805-2?
The four synchronous buck converters supply the main power rails. BUCK1 and BUCK2 can each deliver up to 2.5 A; BUCK3 and BUCK4 each provide up to 1.5 A. All output voltages are independently programmable via I2C, enabling dynamic voltage scaling (DVS) for the CPU core, memory, and I/O domains. This configuration is well‑suited for powering application processors, DDR memory, and peripheral supplies in mid‑range tablets, industrial control panels, and portable instruments.
How many LDOs does the RK805-2 have, and what are they used for?
The RK805‑2 provides 2 general‑purpose low‑dropout linear regulators (LDOs), each typically rated for 200 mA – 300 mA. These low‑noise, low‑ripple outputs supply sensitive analog circuits such as PLLs, USB PHYs, camera modules, and sensor interfaces. Additionally, a dedicated always‑on RTC LDO keeps the system clock and critical registers powered during suspend or power‑off with minimal quiescent current. The compact LDO configuration is perfectly matched to space‑limited designs that only need a couple of clean auxiliary rails.
Does the RK805-2 include a battery charger? What are the charging specifications?
Yes, it integrates a switching battery charger designed for single‑cell Li‑Ion/Li‑Poly batteries. The charging current can be programmed up to 2 A. It supports constant‑current/constant‑voltage (CC/CV) charging, battery temperature monitoring, automatic power‑path management, and a built‑in fuel gauge for capacity estimation. The charger input is separate from the system input, allowing the device to operate and charge simultaneously — a key feature for always‑on industrial tablets and portable medical equipment.
How do I control the RK805-2, and what is its I2C address?
All configuration and status monitoring are performed through a standard I2C serial interface operating at up to 400 kHz. The default 7‑bit I2C address is 0x18 (write). The host SoC can read and write internal registers to set output voltages, enable or disable individual power channels, adjust charging parameters, and read power‑good and fault status. This allows fine‑grained power management, including dynamic voltage scaling (DVS) and selective rail shutdown during sleep modes, extending battery life in portable applications.
What protection features does the RK805-2 include?
The RK805‑2 incorporates comprehensive hardware protections to ensure safe and reliable operation. Each DCDC and LDO channel features cycle‑by‑cycle over‑current protection (OCP). Global protections include over‑temperature protection (OTP) with hysteresis, under‑voltage lockout (UVLO) on the main input, battery over‑voltage / over‑discharge protection, and a thermal shutdown mechanism. A power‑good (PG) output and an interrupt pin alert the host processor to any anomalies, making the device suitable for industrial, automotive accessory, and medical applications.
What is the input voltage range, and what supplies can power the RK805-2?
The main system input voltage range is 2.7 V to 5.5 V, making it directly compatible with USB 5 V rails, single‑cell Li‑Ion batteries (3.0 V – 4.2 V), and standard 3.3 V / 5 V regulated supplies. The charger input accepts 4.5 V – 5.5 V, typically from a USB port or a wall adapter. This wide input flexibility makes the RK805‑2 a versatile choice for both battery‑powered portable devices and always‑on industrial equipment.
What is the QFN‑32 package, and how does it simplify PCB design?
The RK805‑2 is housed in an ultra‑compact QFN‑32 package measuring only 5 mm × 5 mm with a 0.5 mm lead pitch. The exposed thermal pad ensures efficient heat dissipation. The high integration — four bucks, two LDOs, charger, fuel gauge, and RTC — dramatically reduces the component count and PCB area compared to discrete solutions. This tiny footprint makes it a perfect one‑chip power solution for space‑constrained designs such as IoT modules, industrial handheld terminals, and compact medical wearables.
What are the most typical applications for the RK805-2 PMIC?
The RK805‑2 is widely used with Rockchip SoCs such as RK3288, RK3399, PX30, RK3326, and similar processors in portable industrial tablets, smart displays, medical diagnostic tools, IoT gateways, and consumer audio/video players. Its compact size, integrated battery charger, and I2C control make it a popular, cost‑effective power management choice for applications that do not require an on‑chip audio codec and need to fit within a very small PCB area.