XCL208/XCL209 Series
■NOTE ON USE (Continued)
15. In order to stabilize VIN voltage level and oscillation frequency, we recommend that a by-pass capacitor (CIN) be connected
as close as possible to the VIN & VSS pins.
16. High step-down ratio and very light load may lead an intermittent oscillation when PWM mode.
17. For the XCL209, when PWM/PFM automatic switching goes into continuous mode, the IC may be in unstable operation for
the range of MAXDUTY area with small input/output differential. Once the design has been completed, verification with
actual components should be done.
18. Torex places an importance on improving our products and their reliability.
We request that users incorporate fail-safe designs and post-aging protection treatment when using Torex products in their
systems.
19. Instructions of pattern layouts
(1) In order to stabilize VIN voltage level, we recommend that a by-pass capacitor (CIN) be connected as close as possible to
the VIN (No.8) and PVSS (No.1) pins.
(2) Please mount each external component as close to the IC as possible.
(3) Wire external components as close to the IC as possible and use thick, short connecting traces to reduce the circuit
impedance.
(4) Make sure that the PCB GND traces are as thick as possible, as variations in ground potential caused by high ground
currents at the time of switching may result in instability of the IC.
(5) Internal driver transistors bring on heat because of the output current and ON resistance of the driver transistors.
(6) Please connect Lx (No.2) pin and L1 (No.9) pin on the PCB layout.
(7) Please connect VOUT (No.4) pin and L2 (No.10) pin on the PCB layout. (Type A/B)
<Type A/B (VOUT)>
（PCB mounted TOP VIEW）
（TOP VIEW）
（BOTTOM VIEW）
<Type F (FB)>
（PCB mounted TOP VIEW）
（TOP VIEW）
（BOTTOM VIEW）
XCL208/209
XCL208/209
GND
CE
VOUT
CFB
GND
CE
VOUT
CFB
CL
CL
RFB1
RFB1
IC
IC
LX
LX
CIN
CIN
GND
VIN
GND
VIN
TOREX
FB
TOREX
FB
USP-10B03
USP-10B03
: IC
: Ceramic Cap
: Chip Resistance
14/22
TOREX [ Torex Semiconductor ]
