TI PT6902

For assistance or to order, call
Application Notes
Mechanical Outline
Product Selector Guide
(800) 531-5782
PT6900
Series
12 WATT PLUS TO MINUS VOLTAGE
CONVERTER
The PT6900 is a new series of plus to
minus high- performance, 12 watt voltage
converters housed in a 23-pin SIP package.
The PT6900 is designed to supply
regulated negative voltages for powering the latest ECL (-5.2V) and
GaAs (-2.0V) ICs used in high-speed
fiber optic communications. A 330µF
electrolytic capacitor is required on the
input and output for proper operation.
Features
• Single-Device: +5V input
• Remote Sense
• Input Voltage Range:
4.75V to 5.5V
• Adjustable Output Voltage
• 23-pin SIP Package
Pin-Out Information
Standard Application
VADJ
Remote Sense
2
3-7
+VIN
22
PT6900
+
Cin
9-15
16-21
-VOUT
8
Cout
+
GND
GND
Remote Sense
C in = Required 330µF electrolytic
C out = Required 330µF electrolytic
Revised 11/12/98
Ordering Information
PT6901❏
❏ = -2.0 Volts
❏ = -5.2 Volts
PT6902❏
Pin Function
Pin
Function
1
Do not connect
13
GND
2
Vout Adjust
14
GND
3
Vin
15
GND
4
Vin
16
Vout
5
Vin
17
Vout
6
Vin
18
Vout
7
Vin
19
Vout
8
Remote Sense GND
20
Vout
9
GND
21
Vout
10
GND
22
Remote Sense Vout
11
GND
23
Do not connect
12
GND
PT Series Suffix (PT1234X)
Case/Pin
Configuration
Vertical Through-Hole
Horizontal Through-Hole
Horizontal Surface Mount
N
A
C
(For dimensions and PC board layout,
see Package Styles 1100 and 1110.)
Note: Case must be connected to
ground pins for proper operation
Specifications
PT6900 SERIES
Characteristics
(Ta= 25°C unless noted)
Symbols
Output Current
Io
Conditions
Min
Typ
Max
Units
Vo = -2.0V
Vo = -5.2V
0.1 *
0.1 *
—
—
6
2.5
A
A
Ta = +25°C, natural convection Vo = -2.0V
Vo = -5.2V
0.1 *
0.1 *
—
—
6
2.5
A
A
Ta = +60°C, 200 LFM, pkg N
Input Voltage Range
Vin
0.1A ≤ I o ≤ Imax
4.75
—
5.5
V
Output Voltage Tolerance
∆Vo
Vin = +5V, Io = Imax
0°C ≤ Ta ≤ +60°C
Vo-0.05
—
Vo+0.05
V
Line Regulation
Regline
4.75V ≤ Vin ≤ 5.5V, Io = Imax
—
±0.5
±1.0
%
Load Regulation
Regload
Vin = +5V, 0.1 ≤ Io ≤ Imax
—
±0.5
±1.0
%
Vo Ripple/Noise
Vn
Vin = +5V, Io = Imax
Vo = -2.0V
Vo = -5.2V
—
—
40
100
—
—
mV
mV
Transient Response
with Cout = 330µF
t tr
Vos
Io step between 0.5xImax and Imax
Vo over/undershoot
Vo = -2.0V
Vo = -5.2V
—
—
—
100
100
200
—
—
—
µSec
mV
mV
Efficiency
η
Vin = +5V, Io = 0.5xI max,
—
70
—
%
Switching Frequency
ƒo
4.75V ≤ Vin ≤ 5.5V
0.1A ≤ I o ≤ Imax
500
—
—
kHz
Absolute Maximum
Operating Temperature Range
Ta
—
0
—
+85
°C
Recommended Operating
Temperature Range
Ta
Forced airflow = 200 LFM
Over Vin and Io Ranges
0
—
+60
°C
Vo = -2.0V
Storage Temperature
Ts
—
-40
—
+125
°C
Weight
—
Vertical/Horizontal
—
28/33
—
grams
* ISR-will operate down to no load with reduced specifications. Please note that this product is not short-circuit protected.
28
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
For assistance or to order, call
PT6900
CHARACTERISTIC
(800) 531-5782
Series
DATA
Efficiency vs Output Current (@Vin=+5V)
Efficiency - %
80
70
60
50
40
0
1
2
3
4
5
6
5
6
Iout-(Amps)
Ripple vs Output Current (@Vin=+5V)
35
Ripple-(mV)
30
25
20
15
10
5
0
0
1
2
3
4
Iout-(Amps)
Power Dissipation vs Output Current
7
PD-(Watts)
6
5
4
3
2
1
0
0
1
2
3
4
5
6
Iout-(Amps)
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
29
DATA SHEETS
5V5V
to Bus
3.x Converters
Products
PT6901, -2.0 VDC
For assistance or to order, call
Application
Notes
(800) 531-5782
PT6900 Series
More Application Notes
The negative output voltage of the Power Trends PT6900 Series ISRs may be adjusted higher or lower than the factory
trimmed pre-set voltage with the addition of a single external
resistor. Table 1 accordingly gives the allowable adjustment
range for each model in the series as Va (min) and Va (max).
Figure 1
22
Vo(sense)
Refer to Figure 1 and Table 2 for both the placement and value
of the required resistor, either (R1) or R2 as appropriate.
Notes:
1. Use only a single 1% resistor in either the (R1) or R2 location. Place the resistor as close to the ISR as possible.
2. Never connect capacitors from Vo adjust to either GND,
Vout, or the Sense pins. Any capacitance added to the
Vo adjust pin will affect the stability of the ISR.
i.e.
Iout (max)
=
12
Va
Adc,
where Va is the adjusted output voltage.
Vo(adj)
9 - 15
C in
3 3 0 µF
16 - 21
-Vo
Vout(-)
GND(sense)
2
8
(R1)
(Down)
+
R2
(Up)
C out
3 3 0 µF
L
O
A
D
COM
COM
The respective values of (R1) [adjust down], and R2 [adjust up],
can also be calculated using the following formulae.
(R1)
=
24.9 (2Va – Vo)
– Rs
2(Vo – Va)
kΩ
R2
=
24.9 Vo
2(Va – Vo)
kΩ
3. If the sense pins are not being used, the resistors (R1) and R2
can be connected to Vout and GND respectively.
4. An increase in the output voltage must be accompanied by a
corresponding reduction in the maximum output current.
The revised maximum output current must be reduced to
the equivalent of 12Watts.
PT6900
+Vin
GND
Adjust Up:
An increase in the output voltage is obtained by
adding a resistor R2, between pin 2 (Vo adjust) and pin 8
(Remote Sense GND).
Adjust Down: Add a resistor (R1), between pin 2 (Vo adjust) and
pin 22 (Remote Sense Vo).
3-7
+Vin
+
Adjusting the Output Voltage of the
PT6900 Positive to Negative Converter Series
Where:
– Rs
Vo = Original output voltage
Va = Adjusted output voltage
Rs = The resistance given in Table 1
Table1
PT6900 ADJUSTMENT RANGE AND FORMULA PARAMETERS
Series Pt #
PT6903
PT6901
PT6902
Vo (nom)
-1.5V
-2.0V
-5.2V
Va (min)
-1.1V
-1.4V
-3.7V
Va (max)
-2.9V
-4.4V
-8.9V
Ω)
Rs (kΩ
12.7
10.0
17.4
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
3
For assistance or to order, call
(800) 531-5782
Application
PT6900 Series
Notes
Table 2
PT6900 ADJUSTMENT RESISTOR VALUES
Series Pt #
Current
Vo (nom)
Va (req’d)
PT6903
6Adc
–1.5Vdc
PT6902
2.5Adc
–5.2Vdc
Series Pt #
Current
Vo (nom)
Va (req’d)
PT6903
6Adc
–1.5Vdc
PT6901
6Adc
–2.0Vdc
PT6902
2.5Adc
–5.2Vdc
–1.1
(9.1)kΩ
–4.5
(50.2)kΩ
–1.2
(24.7)kΩ
–4.6
(65.6)kΩ
–1.3
(55.8)kΩ
–4.7
(87.2)kΩ
–1.4
(149.0)kΩ
(6.6)kΩ
–4.8
(120.0)kΩ
–1.5
(14.9)kΩ
–4.9
(174.0)kΩ
–1.6
174.0kΩ
(27.4)kΩ
–5.0
(281.0)kΩ
–1.7
80.7kΩ
(48.1)kΩ
–5.1
(605.0)kΩ
–1.8
49.6kΩ
(89.6)kΩ
–5.2
–1.9
34.0kΩ
(214.0)kΩ
–5.3
630.0kΩ
–2.0
24.7kΩ
–5.4
306.0kΩ
–2.1
18.4kΩ
239.0kΩ
–5.5
198.0kΩ
–2.2
14.0kΩ
115.0kΩ
–5.6
144.0kΩ
–2.3
10.6kΩ
73.0kΩ
–5.7
112.0kΩ
–2.4
8.1kΩ
52.3kΩ
–5.8
90.5kΩ
–2.5
6.0kΩ
39.8kΩ
–5.9
75.1kΩ
–2.6
4.3kΩ
31.5kΩ
–6.0
63.5kΩ
–2.7
2.9kΩ
25.6kΩ
–6.2
47.3kΩ
–2.8
1.7kΩ
21.1kΩ
–6.4
36.5kΩ
–2.9
0.6kΩ
17.7kΩ
–6.6
28.8kΩ
–3.0
14.9kΩ
–6.8
23.1kΩ
–3.1
12.6kΩ
–7.0
18.6kΩ
–3.2
10.8kΩ
–7.2
15.0kΩ
–3.3
9.2kΩ
–7.4
12.0kΩ
–3.4
7.8kΩ
–7.6
9.6kΩ
–3.5
6.6kΩ
–7.8
7.5kΩ
–3.6
5.6kΩ
–8.0
5.7kΩ
–3.7
4.7kΩ
(0.9)kΩ
–8.2
4.2kΩ
–3.8
3.8kΩ
(3.9)kΩ
–8.5
2.2kΩ
–3.9
3.1kΩ
(7.5)kΩ
–8.9
0.1kΩ
–4.0
2.5kΩ
(11.7)kΩ
–4.1
1.9kΩ
(16.6)kΩ
–4.2
1.3kΩ
(22.4)kΩ
–4.3
0.8kΩ
(29.6)kΩ
–4.4
0.4kΩ
(38.6)kΩ
R1 = (Red)
4
PT6901
6Adc
–2.0Vdc
R2 = Black
Power Trends, Inc. 27715 Diehl Road, Warrenville, IL 60555 (800) 531-5782 Fax: (630) 393-6902 http://www.powertrends.com
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