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PB_Q24T35_02_12_01
Industry-Standard Quarter-Brick Format
Q24T35 Family
18 Vdc - 36 Vdc In, 35A
Product Brief
The Q24T35 family of through-hole DC/DC converters offers unprecedented performance
in the industry-standard quarter-brick format. This is accomplished through the use of
patent pending circuit and packaging techniques to achieve ultra-high efciency,
excellent thermal performance and very low prole. In thermal environ-
ments common to telecommunications applications, the QTM Series
35A modules provide thermal performance that far exceeds all
quarter-bricks and is comparable even to existing “half-bricks”,
and all this in a height of only 0.29”. Low prole and the pre-
clusion of heatsinks minimizes airow “shadowing”, thus enhancing
cooling for down-stream devices. The use of 100% surface-mount tech-
nologies for assembly, coupled with di/dt’s advanced electric and thermal cir-
cuitry and packaging, result in products with extremely high quality and reliability.
The Q24T35 family is available in ve standard output voltages ranging from 3.3V to 1.5V.
Q24T35 MODULE
Complete efciency and thermal curves for each output voltage are
available upon request.
Features
• Delivers up to 35A
• Delivers higher current at 70°C than
existing 20A and 25A modules deliver at
40°C to 50°C
• Delivers performance comparable to
Half-Bricks in telecom thermal environments
• Industry-Standard footprint
• No Heatsink Required
• Height Only 0.29” (7.2mm)
• Weight: 27g (0.95oz)
• High Efciency: 89% @ 20A
• Industry-Standard size: 1.45” x 2.30”
• 2000V I/O Isolation
• Fixed Frequency Operation
• No Minimum Load Required
• Fully Protected
• Remote Sense
• Adjustable Output Voltage: +10%/-20%
• Industry-Standard external resistor values
• High Reliability
• Remote On/Off
• UL 1950, EN 60950 (pending)
Applications
• Telecommunications
• Datacommunications
• Wireless
EFFICIENCY
@ 20A
3.3V
2.5V
2.0V
1.8V
1.5V
OUTPUT CURRENT
@70°C, 200 LFM
OUTPUT
VOLTAGE
89.1%
87.7%
86.2%
85.0%
84.0%
22.5A
24.5A
26.5A
27.0A
28.0A
Industry-Standard Quarter-Brick Format
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PB_Q24T35_02_12_01
For more information please contact
di/dt, Inc.
1822 Aston Avenue •• Carlsbad, CA •• 92008 •• USA
USA Toll Free 866-WOW-didt (969-3438)
www.didt.com •• support@didt.com
The information and specications contained in this data sheet are believed to be accurate and reliable at the time of publication. However, di/dt, Inc. assumes no responsibility for its use nor
for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of di/dt, Inc.
Specications are subject to change without notice.
Copyright © 2001 di/dt, Inc.
The example above describes P/N Q24T35033P: 24V input voltage, through-hole mounting scheme, 35A output current, 3.3V output voltage and positive enable logic
Converter Part Numbering Scheme
PRODUCT
SERIES
INPUT
VOLTAGE
MOUNTING
SCHEME
RATED OUTPUT
CURRENT
OUTPUT
VOLTAGE
POS / NEG
ENABLE LOGIC
CLEARANCE
OFF USER BOARD
SPECIAL
FEATURES
Q 24 T 35 033 P L
Quarter-Brick
Format 24 - (18V-36V) T - through-hole 35 - 35 Amps Blank - Std.
033 - 3.3V
025 - 2.5V
020 - 2.0V
018 - 1.8V
015 - 1.5V
P - Positive
N - Negative
L - 0.030”
H - 0.060”
Q24T35 Mechanical Drawing
• All dimensions are in inches [mm]
• Pins 1-3 and 5-7 are 0.040”
[01.02mm] diameter with 0.078”
[01.98mm] shoulder.
• Pins 4 and 8 are 0.062”
[01.02mm] diameter without shoulder.
• Pins material: Brass
• Pin Finish: Tin/Lead over Nickel
• Module Weight: 0.95 oz. [27 g]
PIN # FUNCTION
2
4
6
8
1
3
5
7
Vin (+)
Remote On/Off
Vin (-)
Vout (-)
Sense (-)
Trim
Sense (+)
Vout (+)
PIN CONNECTIONS
Note: Option #2 provides minimum 0.060” clearance between the lowest component on the bottom of the module and the user’s circuit board to
provide adequate clearance in instances where Vin traces run directly beneath the module.