RT8259

1.2A, 24V, 1.4MHz Step-Down Converter

The RT8259 is a high voltage buck converter that can support the input voltage range from 4.5V to 24V and the output current can be up to 1.2A. Current Mode operation provides fast transient response and eases loop stabilization.
The chip also provides protection functions such as cycle-by-cycle current limiting and thermal shutdown protection. The RT8259 is available in a SOT-23-6 and TSOT-23-6 packages.

Applications

Distributed Power Systems
Battery Charger
Pre-Regulator for Linear Regulators
WLED Drivers

Key Spec.
	RT8259
Status	Active
Vin (min) (V)	4.5
Vin (max) (V)	24
Number of Outputs	1
Vout (min) (V)	0.8
Vout (max) (V)	15
Output Adj. Method	Resistor
Iout (max) (A)	1.2
Current Limit (typ) (A)	2.1
Freq (typ) (kHz)	1400
Ext Sync	No
Ron_HS (typ) (mOhm)	300
Ron_LS (typ) (mOhm)	300
Iq (typ) (mA)	0.55
Features	Current Mode Control;Cycle-by-Cycle Current Limit;Enable Input;Force PWM;Internal Compensation;OCP;OTP;Stable with Ceramic Capacitor;UVP
Package Type	SOT-26;TSOT-26

Features

Wide Operating Input Voltage Range : 4.5V to 24V
Adjustable Output Voltage Range : 0.8V to 15V
1.2A Output Current
0.3Ω Internal Power MOSFET Switch
High Efficiency up to 92%
1.4MHz Fixed Switching Frequency
Stable with Low ESR Output Ceramic Capacitors
Thermal Shutdown
Cycle-By-Cycle Over Current Protection
RoHS Compliant and Halogen Free

Datasheet
Title	Version	Last Update	Download
RT8259: 1.2A, 24V, 1.4MHz Step-Down Converter	V3.0	2011/12/19

Technical Documents
Title	Item Type	Last Update
Richtek Product Selection Guide [Jan., 2024]	Selection Guide	2024/01/18
Richtek Featured Product Tree [Aug., 2023]	Selection Guide	2023/08/07
Multi-Source Power Management Design	App. Note	2022/04/26

Videos
Title	Last Update	Views
How to estimate control loop bandwidth from the transient response time?	2017/03/30	2677

Reference Design
Title	Last Update	Download
Richtek Load Transient Tool	2022/07/25

Part Number	Package Type	Package Qty.	Free Sample	Distributor	Stock	Buy From Authorized Distributor
RT8259GE	SOT-26	3,000	Request	Digikey	12,138	Buy
RT8259GE	SOT-26	3,000	Request	Mouser	5,638	Buy
RT8259GJ6	TSOT-26	3,000	Request	Digikey	4,685	Buy
RT8259GJ6	TSOT-26	3,000	Request	Mouser	2,790	Buy

Please confirm with our distributor or sales representative for actual stock status.