PTB48500 Datasheet, PDF (2/14 Pages) Texas Instruments – Dual-Output, 48-V Input Isolated DC/DC Converter for xDSL

PTB48500, PTB48501, PTB48502
Dual-Output, 48-V Input Isolated
DC/DC Converter for xDSL
SLTS218B - SEPTEMBER 2003 - REVISED NOVEMBER 2004
Ordering Information
Base Part No. (PTB4850❒xxx)
Output Voltage (PTB4850x❒xx) Package Options (PT4850xx❒❒)
Order Prefix Description
Code
PTB48500xxx 13 A
(32-Ports) A
PTB48501xxx 16.5 A
(48/64-Ports)
PTB48502xx 21 A (64-Ports + 10 W)
Voltage
3.3 V / 1.2 V
Code
AH
AS
Description
Horiz. T/H
SMD, Standard ⁽²⁾
Pkg Ref. ⁽¹⁾
(ERH)
(ERJ)
Notes: (1) Reference the applicable package reference drawing for the dimensions and PC board layout
(2) “Standard” option specifies 63/37, Sn/Pb pin solder material.
Pin Descriptions
+V_I: The positive input supply for the module with respect
to –V_in. When powering the module from a –48 V telecom
central office supply, this input is connected to the primary
system ground.
–V_I: The negative input supply for the module, and the
0 VDC reference for the ‘Enable’, ‘EN Out’, and ‘Sync
Out’ signals. When the module is powered from a +48-V
supply, this input is connected to the 48-V Return.
V_O 1: The higher regulated power output voltage, which
is referenced to the COM node.
V₀ 2: The lower regulated power output voltage, which
is referenced to the COM node.
COM: The secondary return reference for the module’s two
regulated output voltages. It is dc isolated from the input
supply pins.
V_O 2 Adjust: Using a single resistor, this pin allows Vo₂ to
be adjusted higher or lower than the preset value. If not
used, this pin should be left open circuit.
Enable: This is an open-collector (open-drain) positive
logic input that enables the module output. This pin is
referenced to -Vin. A logic ‘0’ at this pin disables the
module’s outputs, and a high impedance enables the out-
puts. If not used the pin should be left unconnected.
EN Out: This open-collector output may be used to enable
the output of other DC/DC converters in applications
where the power-up sequence of the related voltages must
be precisely controlled. The output is used principally to
control the startup up of a PTB4851xx module when
powering ADSL circuits based on the AC7 chipset. The
signal is referenced to -Vin, and is active low. It is initially
‘off’ (high impedance), and turns ‘on’ when the output
voltage, Vo₁, has risen to its nominal set-point voltage.
Sync Out: The signal generated by this pin is designed to
be used exclusively with the PTB48510 in AC7 ADSL
applications. When the ‘Sync Out’ of this converter is
connected directly to the ‘Sync In’ pin of the PTB48510,
both modules will operate at the same switch conversion
frequency.
POR*: (Available to PTB48500 and PTB48501 only!)
This pin produces an active-low power-on reset signal
that may be used to reset logic circuitry. The output is
set low during power up just as the output voltage from
Vo₁ starts to rise. It remains low for 10 ms after the volt-
age at Vo₁ has reached its nominal set-point voltage.
This signal is referenced to the COM node, and has a
3.3-kΩ internal pull-up resistor to Vo₁.
Environmental and General Specifications (Unless otherwise stated, all voltages are with respect to –Vin)
Characteristics
Symbols
Conditions
Min
Typ
Input Voltage Range
Isolation Voltage
Capacitance
Resistance
Operating Temperature Range
Over-Temperature Protection
Solder Reflow Temperature
Storage Temperature
Mechanical Shock
Mechanical Vibration
Weight
Flammability
V_in
Ta
OTP
Treflow
T_s
—
—
Over output load range
36
48
Input–output/input–case
Input to output
Input to output
1500
—
—
1500
10
—
Over Vin Range
–40
—
Shutdown threshold
Hysterisis
—
115
—
10
Surface temperature of module body or pins
—
–40
—
Per Mil-STD-883D, Method 2002.3
1 msec, ½ Sine, mounted
—
500
Mil-STD-883D, Method 2007.2
Suffix H —
20
20-2000 Hz
Suffix C —
5
—
20
Meets UL 94V-O
Max
75
—
—
—
+85
—
—
235 (i)
125
—
—
—
—
Units
VDC
V
pF
MΩ
°C
°C
°C
°C
G’s
G’s
grams
Notes: (i) During reflow of SMD package version do not elevate peak temperature of the module, pins or internal components above the stated maximum.
For technical support and further information visit http://power.ti.com