SLVS302B December 2000 – October 2015 TPS60300 , TPS60301 , TPS60302 , TPS60303
PRODUCTION DATA.
NOTE
Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.
The TPS6030x is a switched capacitor voltage converter providing low noise, constant-frequency linear regulation mode. It supports regulated output voltages of 3 V and 3.3 V from a 0.9-V to 1.8-V input voltage range.
The complete charge pump circuitry requires no inductors and only five small 1-µF ceramic capacitors. It is possible to only use 1-µF capacitors of the same type.
The values of the five external capacitors of the TPS6030x charge pumps are closely linked to the required output current and the output noise and ripple requirements.
For the maximum output current and best performance, five ceramic capacitors with a minimum value of 1 µF are recommended. This value is necessary to assure a stable operation of the system due to the linear mode. For lower currents or higher allowed output voltage ripple, other capacitors can be used. With flying capacitors lower than 1 µF, the maximum output power will decrease. This means that the device will work in the linear mode with lower output currents.
The input capacitor improves system efficiency by reducing the input impedance and stabilizing the input current.
The minimum required capacitance of the output capacitor (COUT) that can be selected is 1 µF. Depending on the maximum allowed output ripple voltage, larger values can be chosen. Table 1 shows capacitor values recommended for low output voltage ripple operation. A recommendation is given for the smallest size.
VIN
[V] |
IOUT(OUT2)
[mA] |
CIN
[µF] |
CXF
[µF] |
COUT
[µF] |
VP-P [mV] At 20 mA / VIN = 1.1 V |
---|---|---|---|---|---|
CERAMIC | CERAMIC | CERAMIC | |||
0.9...1.8 | 0...20 | 1 | 1 | 1 | 16 |
0.9...1.8 | 0...20 | 1 | 1 | 2.2 | 10 |
0.9...1.8 | 0…20 | 1 | 1 | 10 // 0.1 | 6 |
MANUFACTURER | PART NUMBER | SIZE | CAPACITANCE | TYPE |
---|---|---|---|---|
Taiyo Yuden | UMK212BJ104MG LMK212BJ105KG LMK212BJ225MG JMK316BJ475KL |
805 805 805 1206 |
0.1 µF 1 µF 2.2 µF 4.7 µF |
Ceramic Ceramic Ceramic Ceramic |
AVX | 0805ZC105KAT2A 1206ZC225KAT2A |
805 1206 |
1 µF 2.2 µF |
Ceramic Ceramic |
Table 3 lists the manufacturers of recommended capacitors. However, ceramic capacitors will provide the lowest output voltage ripple due to their typically lower ESR.
MANUFACTURER | CAPACITOR TYPE | INTERNET |
---|---|---|
Taiyo Yuden | X7R/X5R ceramic | www.t-yuden.com |
AVX | X7R/X5R ceramic | www.avxcorp.com |
Vishay | X7R/X5R ceramic | www.vishay.com |
Kemet | X7R/X5R ceramic | www.kemet.com |
TDK | X7R/X5R ceramic | www.component.tdk.com |
The power-good output is capable of driving light loads up to 5 mA (see Figure 4). Therefore, the output resistance of the power-good pin, in addition with an output capacitor, can be used as an RC-filter.
Due to R(PG,1), an output filter can easily be formed with an output capacitor (CPG). Cut-off frequency is given by:
with R(PG,1) = 15 Ω, C(PG) = 0.1 µF and f = 600 kHz (at nominal switching frequency)
Load current sourced by power-good output reduces maximum output current at OUT2. During start-up (power good going high) current charging C(PG) will discharge C(OUT2). Therefore, C(PG) must not be larger than 0.1 C(OUT2) or the device will not start. By charging C(PG) through C(OUT2), the output voltage at OUT2 will decrease. If the capacitance of C(PG) is to large, the circuit will detect power bad. The power-good output will go low and discharge C(PG). Then the cycle starts again. Figure 5 shows a configuration with an LC-post filter to further reduce output ripple and noise.
VIN
[V] |
IO(OUT2)
[mA] |
CIN[µF] | CXF[µF] | COUT[µF] | LP[µH] | CP[µF] | VP(OUT)
VP-P[mV] |
---|---|---|---|---|---|---|---|
CERAMIC | CERAMIC | CERAMIC | CERAMIC | ||||
0.9...1.8 | 20 | 1 | 1 | 1 | 0.1 | 0.1 (X7R) | 16 |
0.9...1.8 | 20 | 1 | 1 | 1 | 0.1 | 1 // 0.1 (X7R) | 12 |
0.9...1.8 | 20 | 1 | 1 | 1 | 1 | 0.1 (X7R) | 14 |
0.9...1.8 | 20 | 1 | 1 | 10 | 1 | 1 // 0.1 (X7R) | 3 |