Diodes ZXLD1370 - Manual (Page 5)

ZXLD1370
Document number: DS32165 Rev. 5 - 2
5 of 39
www.diodes.com
September 2012
© Diodes Incorporated
ZXLD1370
A Product Line of
Diodes Incorporated
Recommended Operating Conditions
(@T
A
= +25°C, unless otherwise specified.)
Symbol Parameter Performance/Comment Min Max Unit
V
IN
Input supply voltage range
Normal operation 8
60 V Reduced performance operation
(Note 7)
6.3
V
AUX
Auxiliary supply voltage range (Note 8)
Normal operation 8
60 V Reduced performance operation
(Note 7)
6.3
V
ISM
Current sense monitor input range 6.3 60 V
V
SENSE
Differential input voltage V
VIN
-V
ISM
, with 0 ≤ V
ADJ
≤ 2.5 0 450 mV
V
ADJ
External dc control voltage applied to ADJ
pin to adjust output current DC brightness control mode
from 10% to 200%
0.125 2.5 V
I
REF
Reference external load current REF sourcing current 1 mA
f
max
Recommended switching frequency range
(Note 9)
300 1000 kHz
V
TADJ
Temperature adjustment (T
ADJ
) input voltage range 0 V
REF
V
f
PWM
Recommended PWM dimming frequency range
To achieve 1000:1 resolution 100 500 Hz
To achieve 500:1 resolution 100 1000 Hz
t
PWMH/L
PWM pulse width in dimming mode PWM input high or low 0.002 10 ms
V
PWMH
PWM pin high level input voltage 2 5.5 V
V
PWML
PWM pin low level input voltage 0 0.4 V
T
J
Operating Junction Temperature Range -40 125 °C
GI Gain setting ratio for boost and buck-boost modes Ratio = V
GI
/V
ADJ
0.20 0.50
Notes: 7. Device starts up above 6V and as such the minimum applied supply voltage has to be above 6.5V (plus any noise margin). The ZXLD1370 will,
however, continue to function when the input voltage is reduced from ≥ 8V down to 6.3V.
When operating with input voltages below 8V the output current and device parameters may deviate from their normal values; and is dependent on
power MOSFET switch, load and ambient temperature conditions. To ensure best operation in Boost and Buck-Boost modes with input voltages, V
IN
,
between 6.3 and 8V a suitable boot-strap network on V
AUX
pin is recommended.
Performance in Buck mode will be reduced at input voltages (V
IN
, V
AUX
) below 8V. – a boot-strap network cannot be implemented in buck mode.
8. V
AUX
can be driven from a voltage higher than V
IN
to provide higher efficiency at low V
IN
voltages, but to avoid false operation; a voltage should
not be applied to V
AUX
in the absence of a voltage at V
IN
.
9. The device contains circuitry to control the switching frequency to approximately 400kHz. The maximum and minimum operating frequency is not
tested in production.