The JTMT8823 integrates dual step-down, constant-on-time,

1.产品概述 2.产品特点 3.应用范围 4.下载产品资料PDF文档
5.产品封装图 6.电路原理图 7.功能概述 8.相关产品

一,产品概述(General Description)

The JTMT8823 integrates dual step-down, constant-on-time,
synchronous PWM controllers (that drives dual N-channel MOSFETs for
each channel) and two low drop-out regulators as well as various protections
into a chip.The PWM controllers step down high voltage of a battery
to generate low-voltage for NB applications. The output of PWM1 and
PWM2 can be adjusted from 2V to 5.5V by setting a resistive voltage-divider
from VOUTx to GND.The linear regulators provide 5V and 3.3V output for
standby power supply. The linear regulators provide up to 100mA output
current. When the PWMx output voltage is higher than LDOx bypass threshold, the related LDOx regulator is shut off and its output is connected to VOUTx
by internal switchover MOSFET. It can save power dissipation. The charge
pump circuit with 250kHz clock driver uses VOUT1 as its power supply to generate ap-proximately 15V DC voltage.
The JTMT8823 provides excellent transient response and accurate DC output voltage in either PFM or PWM Mode. In Pulse-Frequency Mode (PFM),
the JTMT8823 provides very high efficiency over light to heavy loads

with loading-modulated switching frequencies. The Forced-PWM Mode works nearly at constant frequency for low-noise requirements. The unique ultrasonic
mode maintains the switching frequency above 25kHz, which eliminates noise in audio application.The JTMT8823A/D has individual enable controls for
each PWM channels. Pulling both EN1/2 pin low shuts down the all of outputs unless LDO3 output. The LDO3 and LDO5 of JTMT8823B/C are always on standby power.The JTMT8823 is available in a TQFN3x3-20 package.

二.产品特点(Features)
Wide Input voltage Range from 5.5V to 25V
Provide 5 Independent Outputs with ±1.0% Accu-racy Over-Temperature
PWM1 Controller with Adjustable (2V to 5.5V) Out-put
- PWM2 Controller with Adjustable (2V to 5.5V) Out-put
100mA Low Dropout Regulator (LDO5) with Fixed 5V Output
- 100mA Low Dropout Regulator (LDO3) with Fixed 3.3V Output
250kHz Clock Signal for 15V Charge Pump (Used PWM1 as Its Power Supply)
Excellent Line/Load Regulations about±1.5% over
temperature range at PWM Channels
Low Consumption in Standby Mode
2Cells Input Battery Support
Built in POR Control Scheme Implemented
Constant On-Time Control Scheme
Built in Soft Start for PWM Outputs and Soft Stop
for PWM Outputs and LDO Outputs
Integrated Bootstrap Forward P-CH MOSFET
High Efficiency over Light to Full Load Range (PWMs)
Built in Power Good Indicators (PWMs)
60% Under-Voltage and 115% Over-Voltage Protec-tions (PWM)
Adjustable Current-Limit Protection (PWMs)
- Using Sense Low-Side MOSFET’s RDS(ON)
Over-Temperature Protection
3mmx3mm Thin QFN-20 (TQFN3x3-20) package
Lead Free and Green Device Available (RoHS Compliant)

三,应用范围 (Applications)
Notebook and Sub-Notebook Computers
Portable Devices
DDR1, DDR2, and DDR3 Power Supplies
3-Cell and 4-Cell Li+ Battery-Powered Devices
Graphic Cards
Game Consoles
Telecommunications

四.下载产品资料PDF文档

JTMT8823

五,产品封装图 (Package)

六.电路原理图