RY8310

Email: support@rychip.com

http://www.rychip.com

©RYCHIP Semiconductor Inc.

30V 1.2A 1.4MHz Synchronous Step-Down Regulator

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Functional Block Diagram

VCC REGULATOR

OSCILLATOR

REFERENCE

1M

400k

56pF

1pF

COMPARATOR

ON TIME CONTROL

LOGIC CONTROL

∑

BOOST

REGULATOR

HS

DRIVER

LS

DRIVER

VCC

VCC

IN

EN

FB

GND

SW

BS

CURRENT LIMIT

COMPARATOR

+

+

-

CURRENT SENSE

AMPLIFIER

RSEN

ERROR AMPLIFIER

+

-

+

-

+

-

+

-

VCC REGULATOR

OSCILLATOR

REFERENCE

1M

400k

56pF

1pF

COMPARATOR

ON TIME CONTROL

LOGIC CONTROL

∑

BOOST

REGULATOR

HS

DRIVER

LS

DRIVER

VCC

VCC

IN

EN

FB

GND

SW

BS

CURRENT LIMIT

COMPARATOR

+

+

-

CURRENT SENSE

AMPLIFIER

RSEN

ERROR AMPLIFIER

+

-

+

-

Block Diagram

Functions Description

Internal Regulator

The RY8310 is a current mode step down DC/DC converter that provides excellent transient response with no extra

external compensation components. This device contains an internal, low resistance, high voltage power MOSFET,

and operates at a high 1.4MHz operating frequency to ensure a compact, high efficiency design with excellent AC

and DC performance.

Error Amplifier

The error amplifier compares the FB pin voltage with the internal FB reference (VFB) and outputs a current

proportional to the difference between the two. This output current is then used to charge or discharge the internal

compensation network, which is used to control the power MOSFET current. The optimized internal compensation

network minimizes the external component counts and simplifies the control loop design.

Under-Voltage Lockout (UVLO)

Under-voltage lockout (UVLO) protects the chip from operating at an insufficient supply voltage. UVLO protection

monitors the internal regulator voltage. When the voltage is lower than UVLO threshold voltage, the device is shut

off. When the voltage is higher than UVLO threshold voltage, the device is enabled again.

Thermal Shutdown

Thermal shutdown prevents the chip from operating at exceedingly high temperatures. When the silicon die

temperature exceeds 160°C, it shuts down the whole chip. When the temperature falls below its lower threshold

(Typ. 130°C) the chip is enabled again.