6.8 ±6 V analog power (PWR-A6)

PWR-A6 is the power domain of ±6 V for analog circuits, and an optional feature for the products in it: a module with an PWR-A6 entry, a power supply that makes ±6 V for a row, a power converter that makes it for one product from the bus or from PWR-DC12, and the cables between them. A module on PWR-A6 finishes its own regulation, typically ±5 V from a low-dropout regulator per circuit block, so that the drop and pickup of the cable land on the module's regulator headroom and not on its signals. PWR-A6 is separate from the bus (6.4) and from PWR-DC12 (6.7); the rules common to every domain are in 6.1 to 6.3, and the ripple limit of PWR-A6 is in the table of 6.2. The figures are in data/analog_6.json.

EIS · PWR-A6: the A6-VH3 entry and the voltage window polarizing rib 1 +6 V 2 0 V 3 −6 V A6-VH3 from the mating side, 3.96 mm pitch 10 A per circuit; 1 A per rail at an entry 5.0 V 5.5 V 6.0 V 6.5 V outlet 5.75–6.25 module entry 5.55–6.25 cable ≤ 0.2 V withstood 6.6 V a module's ±5 V LDO One connector for PWR-A6 only (A6-001). An outlet holds its window to its rating (A6-002); a module works across the entry window (A6-003), survives 6.6 V (A6-004), and draws at most 1 A per rail (A6-005).

Connector and pins

A PWR-A6 entry or outlet shall be an A6-VH3 connector, a JST VH 3-circuit header on a 3.96 mm pitch with its polarized housing, with the pin functions tabulated below (A6-001). No other EIS domain uses a 3-circuit VH; a DC-VH2 housing fits two of its pins, which is why the ±6 V mark beside the connector matters (A6-007) and why an entry withstands 6.6 V and no more (A6-004). A PWR-A6 entry or outlet shall be marked ±6 V beside it (A6-007). The header and housing named are reference parts; an interchangeable part rated for the published current may be used.

Variant Header (reference) Mating housing (reference) Rated per circuit (A)
A6-VH3 JST B3P-VH (straight) or B3PS-VH (right angle) 3-circuit header JST VHR-3N housing with SVH-21T-P1.1 crimp terminals 10

A6-VH3 pins

Pin Function
1 +6 V
2 0 V
3 −6 V

Voltage window

A PWR-A6 outlet shall hold each rail between 5.75 V and 6.25 V in magnitude, from no load to its published rating (A6-002). A module shall meet its published behavior with each rail anywhere from 5.55 V to 6.25 V in magnitude at its entry (A6-003); the 0.2 V between the two windows is the allowance for the cable and the connectors at the entry limit. A PWR-A6 entry shall withstand 6.6 V in magnitude on either rail without damage (A6-004), the start-up overshoot that SUP-006 allows a source.

Figure Value
Nominal ±6 V
At an outlet, no load to rating 5.75 V to 6.25 V
At an entry, where the module meets its behavior 5.55 V to 6.25 V
Withstood at an entry 6.6 V
Ripple and noise at an outlet below 20 mV p-p
Per rail through one entry 1 A
Cable at most 500 mm, at least 22 AWG

EIS recommends that a source clamp its outlet so that a failed pass element cannot put its input voltage on a module, and that a module's entry carry a resettable fuse and a clamp per rail.

Modules

A module shall not draw more than 1 A on either rail through one PWR-A6 entry (A6-005). It publishes its current on each rail as every power entry does (PWR-001). A module that takes its analog rails from PWR-A6 and its logic supply from the bus needs both connected; its entries are not alternatives, and its claim file says so.

Cables

A PWR-A6 cable shall connect each pin to the same pin at both ends, be no longer than 500 mm, and use conductors of at least 22 AWG (A6-006). A power converter mounted on the back of the module it powers connects to the module's entry by such a cable; EIS defines no board-to-board mate.

Sources

A power supply that makes PWR-A6 for a row publishes the current of each outlet and its total (PWR-002), and meets the rules of 6.2 at every outlet. A power converter makes PWR-A6 for one product: from the bus, by stepping each rail down, or from PWR-DC12, which needs an isolated or inverting converter for the negative rail. A linear converter on the bus draws the module's full current from the bus and turns the difference into heat; its published bus current and heat (PWR-001, SUP-008) are what the installer budgets.

EIS recommends a linear or post-regulated source for PWR-A6, typically under 5 mV of ripple and noise.