XC9235 Series

3MHz Synchronous Step-Down DC/DC Converter

XC9235 PWM only
XC9236 PWM/PFM (Auto Switching)
XC9237 PWM only or PWM/PFM (Auto Switching)

The XC9235/XC9236/XC9237 series, is a group of step-down synchronous DC/DC converters with a built-in 0.42 ohm P-channel driver transistor and 0.52 ohm N-channel switching transistor. The ICs provide a high efficiency (Typ 92%) and a stable power supply with output currents of up to 600mA achievable using only a coil and two ceramic capacitors connected externally. Quiescent current is only 15μA.

Minimum operating voltage is 1.8V (D~G types) or 2.0V (A~C types). Output voltage is fixed within a range of 0.8V to 4.0V in 50mV steps (accuracy: ± 2.0%) with the A/B/C/E/G types. With the D/F types, using 0.8V of refrence voltage, output voltage is set externally from 0.9V using external resistors . Switching frequency is selectable from either 1.2MHz or 3MHz. The XC9235 is PWM control, the XC9236 series is automatic PWM/PFM switching control and the XC9237 series can be manually be switched between the PWM and PWM/PFM switching control mode,allowing fast response, low ripple (<10mV) and high efficiency over the full range of load conditions. The soft start and current control functions are internally optimized. Soft-start is 1.0ms typically but a faster soft-start of 0.25ms is available with the B/F/G types.

During standby, all circuits are shutdown to reduce current consumption to as low as 1.0μA or less.

A/B/C versions now available in ultra low profile (0.4mm) USP-6EL Package !

Features:
 

• Input Voltage: 1.8V ~ 6.0V
• Output Voltage: 0.8V ~ 4.0V
• Output Current: 600mA
• Oscillator Frequency: 1.2MHz, 3MHz 
• Compatible with ceramic capacitors
• Built-in soft start circuit
• Built-in current limiter circuit 
• Stand-by Current: 1.0μA (max)
• Small SOT23-5, USP-6C & USP-6EL (2.0 x 1.8 x 0.4mm) Packages
• Only 3 External Components required 

Packages: SOT-25 , USP-6C , USP-6EL