E
7
Technical Specification
EN/LZT 146 420 R3A March 2014
© Ericsson AB
PKB 4000A series Direct Converters
Input 36-72 V, Output up to 30 A / 125 W
3.3V, 30A /99W Typical Characteristics
Start-up
PKB 4910A PI
Shut-down
Start-up enabled by connecting VI at:
TP1 = +25°C, VI = 53 V,
IO = 30 A resistive load.
Top trace: output voltage (1 V/div.).
Bottom trace: input voltage (50 V/div.).
Time scale: (5 ms/div.).
Shut-down enabled by disconnecting VI at:
TP1 = +25°C, VI = 53 V,
IO = 30 A resistive load.
Top trace: output voltage (1 V/div.).
Bottom trace: input voltage (50 V/div.).
Time scale: (50 us/div.).
Output Ripple & Noise
Output Load Transient Response
Output voltage ripple at:
TP1 = +25°C, VI = 53 V,
Trace: output voltage (20 mV/div.).
Time scale: (2 µs/div.).
Output voltage response to load current step- Top trace: output voltage (200 mV/div.).
change (7.5-22.5-7.5 A) at:
Bottom trace: load current (10 A/div.).
Time scale: (0.1 ms/div.).
I
O = 30 A resistive load.
TP1 = +25°C, VI = 53V, Co = 3mF.
Output Voltage Adjust (see operating information)
Passive adjust
Active adjust
The resistor value for an adjusted output voltage is calculated by using
the following equations:
The output voltage may be adjusted using a {current/voltage} applied
to the Vadj pin. This {current/voltage} is calculated by using the
following equations:
Output Voltage Adjust Upwards, Increase:
Vdesired − 3.30
5.1× 3.30
(
100 + ∆%
)
510
Vadj = 1.225 + 2.45 ×
V
Radj =
−
− 10.2 kΩ
3.30
1.225 × ∆%
∆%
Example: Upwards => 3.50 V
Example: Increase 4% =>Vout = 3.432 Vdc
3.50 − 3.30
5.1× 3.30
(
100 + 4
)
510
4
1.225 + 2.45 ×
V = 1.37 V
−
− 10.2 kΩ = 220 kΩ
3.30
1.225 × 4
Output Voltage Adjust Downwards, Decrease:
100
Radj = 5.11×
− 2 kΩ
∆%